sweetpea_gardener23, a plant will wilt when stressed for water but there is 'temporary' wilt and 'permanent' wilt.
If you see the plant wilt during the hottest part of the day but recovers as things cool down the stress has not become severe -yet. But you will observe that it takes longer to recover as time rolls by, until the point of permanent wilt is reached. Then, the plant will not recover. The pore space in the soil holds water and air, both quite necessary for the life of the plant. More water in the soil pores means less air and vice versa. As water gets short the plant has to exert more energy to get it. This leaves less energy for flowering, fruiting etc.
We manage these conditions by the 'simple' decision -to water or not. My grandmother watered the kitchen garden in the afternoon presumably because she was keeping an eye on the tomato plants and their recovery from temporary wilt. She watered the flower garden in the mornings presumably because it prolonged the period of 'morning dew' which was considered to be beneficial to flowers and to toddlers (let the child learn to walk barefoot on grass still wet with morning dew!).
Me? I believe that decisions should be based on measurement. I use a probe.