In Access, when you enter times, you have to use a specific format, (the datetime group specified by the Windows default) rather than just "23:40" or w/e. I've seen a hack where the hour and minutes are separate boxes, but it wasn't pretty. Just this issue was enough to make Access unappealing.

Access's interface is a bit unintuitive, and given that most people I worked with weren't particularly technically capable, I preferred to present them with the familiar Excel interface (and a few extra buttons), rather than teach them an application they've never used before.

Plus, the existing workflow already used Excel, so I hijacked their workflow and their routine wouldn't be modified much at all (introducing a completely new system would cause a lot of friction and pushback, but one or two extra buttons was fine).