Buying has always felt easier to me than selling. I can usually articulate why I’m buying something, but I’ve never had a particularly systematic process for deciding when to reduce a position, rebalance, or admit the thesis has changed.
To force myself into being more disciplined, I started recording a thesis every time I buy: - Why I’m buying - What has to go right - What would invalidate the thesis - Target portfolio weight - Key risks
I also score holdings periodically across things like moat, management, valuation, financials, market opportunity, competition and product quality, and compare changes over time.
The interesting question for me is what to do when a winner becomes a much larger position than originally intended.
One school of thought says: - Trim back to target weight. - Rebalance systematically. - Don’t let a few positions dominate the portfolio.
The other says: - Let winners run. - Most returns come from a handful of exceptional investments. - Rebalancing can mean selling your best ideas to buy worse ones.
I built myself a simple local tool to track this process because spreadsheets were becoming difficult to manage over multi-year holding periods, but before I spend more time on it I’m curious:
- How do you personally decide when to sell or trim? - Do you use target portfolio weights? - Do you formally revisit your thesis? - Has anyone found a tool that genuinely helps with this?
I’d be especially interested in hearing from people who’ve held and rebalanced stocks for 5–10+ years and feel that they are optimising for achieving their personal goals. Thanks!