The material the plant is potted in. The type of plant. No hard rule for watering can be stated. Some homes are drier than others. Small pots dry out faster than large pots.
Some plants prefer more water than others.
Watch the plants, they let you know when they need water. The roots will tell you if you have good watering habits. They're white, firm, and fleshy with green tips in healthy plants. Overwatered plants have few good roots, and many soggy, mushy, brown, dead ones. They set their own schedule.