Alkaline cells are cheap up front and hold their charge for years on the shelf, which makes them ideal for remotes, clocks and emergency torches you rarely use.
Rechargeable cells cost more at first but work out far cheaper for anything you use daily — a torch on a night shift, a toy, or a wireless mouse.
A simple rule: if the device drains a set of cells in under a month, go rechargeable. If a set lasts six months or more, alkaline is the better value.