Episode 18 Compounding Secrets Every Card Collector Misses Ft. Iowa Dave

Released: September 3, 2025 | Duration: 46:17

Prefer audio-only? spotify slabnomics podcast linkslabnomics apple podcasts link

About This Episode

Dave Schwartz hosts The Shallow End podcast, teaches media at a university in Iowa, and has been collecting sports cards since 1983. When he came back into the hobby during COVID, he made the same mistakes most people make: buying unlicensed Panini baseball cards for six months without knowing they were unlicensed, chasing what was exciting rather than what he actually wanted, and selling cards he loved impulsively to fund the next thing he was excited about. He built a podcast to document all of it.

The sports card investing lessons that carry through this conversation are not about which cards to buy. They are about what kind of collector or investor you are building yourself into over time. Compounding applies to knowledge the same way it applies to money. The person who has been making and logging mistakes for five years has a structural edge over the person who just arrived with a bigger budget. The decisions get better. The returns follow.

Dave's best lesson is simple and uncomfortable: he is an impulsive seller. Knowing that about himself has not fully fixed the problem, but it has led him to build in safeguards, people whose judgment he trusts, who will tell him when he is about to do something he will regret.

Topics Covered

  • Dave’s collecting origin: 1983 childhood start, COVID return, six months of buying unlicensed Panini baseball cards without knowing the difference
  • Compound interest applied to knowledge: the same exponential logic that governs money also governs skill and judgment
  • Failure as tuition (the Failing Up series): 18 episodes with 18 different collectors sharing their biggest mistakes
  • Impulsive selling as the primary failure pattern: buys with careful research but sells on impulse; the Ohtani collection as the clearest example
  • The Ohtani lesson: identified Ohtani early, bought a 2021 Heritage Chrome Gold Refractor out of 5 BGS 9.5, then sold for reasons he cannot fully reconstruct; the cards all went higher
  • Investment thesis discipline: the reason to sell a card is the thesis changing, not that something else looks interesting
  • Sleep on it principle revisited: building a network of trusted contacts who act as a circuit breaker before impulsive decisions
  • Collection depth versus breadth: narrowed from five sports to baseball and pre-Panini WNBA (1997-2018)
  • Pre-Panini WNBA collecting: present at the first WNBA game in 1997, proximity to Caitlin Clark’s career at Iowa, focusing on the players who built the league
  • Identity and collection: collections reflect who you are but you are not your collection
  • The integrity story: a $0.61 COMC Albert Pujols purchase that arrived as an artist proof one-of-one; the question of whether to bid on his own mislabeled card
  • Vulnerability in content creation: the memoir approach to podcasting and how openness builds trust

Full Transcript Summary

Compounding Knowledge Works Like Compounding Money

The most famous principle in investing is that compounding makes the first dollars earned the most valuable, because they have the most time to multiply. Dave Schwartz extends this idea to something less discussed: knowledge compounds the same way.

Someone who has been in the sports card hobby for ten years and has made real mistakes with real money has built a foundation that a newcomer with twice the budget cannot buy. Every failed grading play, every impulsive sell, every player who peaked faster than expected and crashed faster than expected, all of that becomes pattern recognition. The loss feels like tuition at the time. Over years, it becomes edge.

Dave Spinrat calls it paying tuition. You were not robbed. You enrolled. The question is whether you attended class. The collectors who attend, meaning the ones who actually sit with their mistakes, figure out what went wrong, and adjust, compound their knowledge the same way good investments compound capital. The ones who move on to the next card without reflection spend the same tuition multiple times for the same lesson.

The Impulsive Seller Problem

Dave's primary failure pattern is not what he buys. He takes time with purchases. He does the research, considers how a card fits into what he actually wants, and thinks about whether the price makes sense. The buying decisions are mostly good.

The selling decisions are not. He moves cards impulsively, often for reasons that do not survive review, and frequently discovers later that the thesis on the card he sold was still intact. The card was right. The timing was wrong. The impulse won.

The clearest example is Shohei Ohtani. Dave identified Ohtani early: multi-continent popularity, doing something no one had done before as a two-way player, charismatic, physically imposing, with a career trajectory that suggested spanning generations. He acquired a 2021 Heritage Chrome Gold Refractor out of 5, BGS 9.5, a difficult card to acquire and a difficult card to replicate. He sold it. He cannot reconstruct exactly why. The best explanation he has is that something else looked more interesting in that moment and the Ohtani position got sacrificed for it.

The card has gone up. He would not sell it today for the money.

The response to recognizing this about himself was not to become a perfect disciplined decision-maker. It was to build in a circuit breaker: two or three people whose judgment he trusts, who he now runs major sell decisions past before executing them. It does not always stop the impulse, but it slows it down enough for logic to have a say.

Investment Thesis as a Discipline

Every card purchase should come with an answer to a question that most collectors never actually formulate: why does this make sense and what would have to change for it to no longer make sense?

If you cannot answer the second part, you do not have a thesis. You have a buy. A thesis includes the conditions under which selling becomes correct. When those conditions change, selling is rational. When those conditions have not changed but something else looks shiny, selling is just impulsive selling with rationalization attached.

Dave's Ohtani cards had a thesis. Multi-continent fan base, generational talent, doing something unprecedented, positioned to grow in the US market. None of those conditions changed when he sold. He just liked something else more in that moment, which is not thesis change. It is distraction.

Depth Over Breadth: Building a Real Collection

At various points Dave had active positions in baseball, basketball, football, soccer, and hockey. At some point that became unmanageable, not because the cards were too much to track but because the attention was spread too thin. You cannot know five markets well enough to have an edge in any of them.

He narrowed to two: baseball across all eras, and pre-Panini WNBA from 1997 through 2018. Both choices are grounded in personal history rather than market timing. Baseball is from St. Louis, where it functions like a religion. The WNBA collection comes from being present at the first game in 1997, having three daughters who played at high levels, living a mile and a half from Carver-Hawkeye Arena during Caitlin Clark's college career, and a career that has taken him through women's athletics in various professional capacities.

The WNBA market has expanded dramatically around Clark, but Dave is not collecting Clark. He is collecting the players who built the league before Clark arrived: Candace Parker, Lisa Leslie, Rebecca Lobo, the names that the current moment is built on top of.

Going deeper on two means knowing those markets well enough to actually find value. Going wider on six means knowing all of them shallowly enough to consistently pay too much and sell too soon.

You Are Not Your Collection

One of the cleaner ideas from this conversation: collections reflect who you are, but you are not your collection.

The distinction matters because collectors who conflate their identity with their portfolio start making decisions that protect the portfolio's story rather than optimizing it. If selling a card feels like admitting something about yourself, you will hold past the right exit. If completing a run feels like proving something, you will overpay for the last piece. The collection becomes a performance rather than a collection.

The practical test: would you buy this card at this price today, knowing nothing about your history with it? If no, the reason to hold it is probably identity, not investment or collector logic.

The Integrity Story

A $0.61 COMC purchase, an Albert Pujols card that arrived as an artist proof parallel one-of-one. Dave did not notice it at first. When he did, he tried to sell it through a consignment service, which labeled it incorrectly. A single bidder was about to win it for essentially nothing because the card's identity was buried in a wrong listing.

The question he had to answer: should he bid on his own card to protect himself?

Jeremy Lee had addressed the topic in a previous conversation: there might be an exception if a card is labeled wrong and you are trying to protect yourself rather than inflate the price. Dave held that possibility while knowing the answer was almost certainly no.

He did not bid. He eventually reached the consignment service, got the card relisted correctly, and ultimately got it back. He still has it.

The principle he articulated is the one that held: assume the whole world is watching and do the right thing. Not because you will get caught. Because the version of yourself who bids on his own card is not a version worth becoming, regardless of whether anyone sees it.

Related Episodes