The minute they leak that there are layoffs coming, every talented individual is going to start spending all their time job hunting instead of working even if t

The minute they leak that there are layoffs coming, every talented individual is going to start spending all their time job hunting instead of working even if they weren't going to be laid off; likewise, untalented individuals will stop giving a shit. You also have security problems if you provide advanced notice. It is inevitable that the data will get leaked which will affect share price before a narrative can be composed, you give vindictive employees time to steal IP, data, or physical goods before they are out the door, and you provide a window of time for people to damage systems. Unfortunately the best way to do it from the company's perspective is to be sudden and surgical, giving people 0 time to sabotage the company.