On the other hand, I did this, cut my cables, and after I needed to reorganise things slightly, it was very difficult, even a centimetre was at luxury. Also, when I need to move a computer for some reason, there’s no room, at all. These days, I’m trying to leave at least some extra cm (usually that’s an inch or two, depending on their location) for that. I’d do very tight cable cut only for situations when I’m super sure nothing will ever move. Again, even then, I’d rather leave some extra inch, just in case.