What am I missing with this trade idea?

Based on the current environment I was looking to possibly start shorting. I like the idea of selling calls. Here’s my question. If I sell a naked call, say on SPY, it will either expire ITM or OTM. If it looks like it will expire ITM, would buying 100 shares just before expiration, thus making it a covered call position, give me any kind of edge on this scenario? the shares will get called away and the position will be closed. In this strategy, Buying the shares last minute would be the protection so that I’m not short 100 shares. Obviously the other way to handle this would be to roll the call, but what am I missing with this “buy the shares last minute” idea? Is this a win/win strategy? If not why not? Thx in advance!