Know the mix
Dense compost holds water differently from a chunky, airy blend. Two identical plants in different mixes may require quite different checks.
Look at the pot
Small terracotta pots often dry differently from large glazed containers. Size, material and drainage all influence how long moisture remains.
Notice the room
Warm moving air, strong light and vigorous new growth can increase water demand. A cool, dim period usually calls for more caution before watering again.
Check the drainage holes
A pot without an escape route needs a different approach. For many common houseplants a drainage hole makes consistent watering much easier.