Why do some Adobe tools behave differently after updates, even with the same settings?

I have noticed that after certain Adobe updates, some tools (like selection, brushes, or shortcuts) don’t behave exactly the same as before even though my preferences and workspace settings look unchanged.

Is this due to under-the-hood improvements, performance optimizations, or compatibility adjustments?
I am curious how other users handle this and whether there is a recommended way to keep workflows consistent after updates.

Has anyone else experienced this, and how do you usually adapt or troubleshoot it?