Portfolio Manager Reveals How Selling a 19-Bagger Too Early Changed His Investment Philosophy Forever

A former Janus analyst said he correctly called for Fastenal stock to sell off, but the firm sold too early and missed the stock's eventual 19x advance. The piece is mainly a retrospective on portfolio decision-making and the cost of premature selling, rather than new company-specific fundamentals. Market impact is limited because it is commentary about an old stock move, not a fresh catalyst.

Analysis

The real signal here is not about one stock’s upside, but about how expensive it is to be structurally correct and tactically early in quality industrial compounders. Fastenal is the kind of business where the distribution network, customer embeddedness, and operating leverage create a long runway for per-share compounding that can overwhelm short-term factor calls; the opportunity cost of exiting after a near-term drawdown can dwarf the original thesis error. In other words, the biggest mistake is often treating valuation compression as thesis invalidation when it may just be mean reversion in sentiment before a multi-year rerating.

Second-order, this reinforces a broader lesson for industrials exposed to MRO and manufacturing capex: the market tends to underwrite earnings cyclicality and underappreciate self-reinforcing share gains from logistics density, SKU breadth, and vendor consolidation. If management keeps taking share in fragmented channels, competitors face a worse mix of price pressure and service intensity, which can extend the leader’s moat rather than cap it. That dynamic matters most over 12-36 months, not in the next quarter, and it is exactly where sell-side forecasting often breaks down.

The contrarian view is that many investors still anchor on last cycle’s multiple and miss the option value embedded in persistent execution. The trade-off is that these names can look ‘too expensive’ for long stretches, so the setup is not a catalyst trade but a patience trade; the risk is not business deterioration, but multiple compression if rates stay higher for longer or industrial PMIs roll over. If the market is rewarding short-duration cash flows again, even excellent operators can underperform for 6-9 months before fundamentals reassert themselves.

Key Decisions for Investors

• Stay long FAST on a 12-24 month horizon; use any 10-15% drawdown as an add point, because the asymmetry is skewed toward missed upside rather than permanent impairment.
• Pair FAST long vs. a lower-quality industrial distributor/industrial supplier basket over the next 6-12 months to isolate moat/compounding alpha from macro beta.
• If already underweight FAST, consider buying call spreads 6-12 months out instead of common stock to express upside with limited time decay while the market digests the compounding story.
• Avoid shorting FAST solely on valuation; if you must hedge, pair any short with a fundamentally weaker peer to avoid getting run over by multiple expansion in a quality squeeze.