When we try a bed in a mattress store, we're awake. Our muscles are actively providing support and balance for our bodies. When we go to sleep, our muscles relax, causing how we lay on the mattress to change. (Kind of like the difference between uncooked and cooked spaghetti.…)
Add to that natural movement through the night and an infinite amount of preferred sleep positions, and it begins to make sense why a bed that felt great in the
store just doesn't feel the same once you get it home.