The same works in reverse.

Example:

Assuming that you start with 100K shares

Buy 10K @ .7

Sell the 10K @.8

Permit is announced and the price goes to $4.00

That $1000 you made selling 10000 shares at .10 profit would have been $33000 had you not sold at .80

You just got yourself additional 1000 shares absolutely free and with no risk involved (only if it went down to again)

You didn’t touch you core investment, and these 1000 shares might worth $20,000 (by using you $20 figure those 10000 shares you sold at .80 would be worth $200000 someday)