What tools do you use to help you decide when to sell?

[nafregnum]

Just sold half of my best performing position ever.  (For the curious, it was ENPH bought in 2017, idea from Dan Loeb 13F)

 

So, how do you go about deciding when it's right to sell?  Any online tools or strategies that have worked well for you?  Do you watch volume figures to help decide?

 

[ If interested in my own small process, this was my internal debate, and how I decided to sell ]

 

Arguments for holding:

 

Part of me thinks it could keep going up for a lot longer during the upcoming Biden years, so I ought to let this winner just keep running.  Along these lines, another temptation to hold comes from Fidelity research that the best performing accounts were from people who forgot about their accounts or were dead so the accounts sat idle for years.  https://twocents.lifehacker.com/the-best-investors-literally-forget-about-their-portfol-1782581085

 

Arguments for selling:

 

I had to fight back these thoughts with Buffettisms like "Buy from pessimists, Sell to optimists" and the decision became final when I checked insider buys/sells and saw that it's all sell for the last few years (the only buys were stock option strike prices of 18 instead of at-the-time prices in 60s) https://www.dataroma.com/m/ins/ins.php?t=y&&sym=ENPH&o=fd&d=d and

 

[scorpioncapital]

sell aggresively if you have debt.

sell if you think you were just lucky.

sell if you find something better or to consolidate 2-3 positions into 1 high conviction, stronger peer.

sell if you get bored by what you hold.

sell if you don't sleep well.