In day-to-day, DIY etc, work I'll nearly always use mm (not cm, as they went west a long time ago!), because it's all so much easier. If, for example, I measured a length at 4 ft 7 1/16 in, and wanted to have 5 equidistant fixings along it, I'd get there, but slowly and doubtfully.
If I measured it at 1398.6 though (no unit mentioned, 'cos it's mm), I'd quickly be able to mark positions every 233.1 and get on with it!
If I measure three lengths and want to add them, then 23 3/16, plus 17 3/4, plus 15 3/10 is unnecessarily difficult. And my old steel rules tend to have 1/4, 1/8 and 1/16 markings at one end, and 1/10 inch at the other ...
I recently had to work in inches, to make a fleecy wrap for my great niece for Christmas ... because my cutting board and roller-cutter guide are American. It was horrible, until I redesigned it to have all parts in whole inches, all hems at 1/2 inch - and screw the finer aesthetics!
Only where the item has been designed in specific inches is there any advantage - or joy - in using them.