It is upon this bed that you shall dream the dreams from which your life shall be woven anew. Also: drooling.
The long night of watching old movies. The long day when you can't shake that fever. The long afternoon with someone you love. The long evening when nobody understands you but a tub of ice cream. The long midday before you get your grades. The long twilight before you meet your future in-laws. These are the days and times when you'll be needing to lie down, and when you'll be happiest that your mattress is soft, comfy and cool.
Yes, it'll be the place where you sleep, but you won't be noticing much when you're asleep. But when you're sad, or mad, or stressed, or happy, or emotional, that's when you'll be aware if your mattress is uncomfortable.
We all turn to our beds in times of need. So make sure said bed is ready to support you. Otherwise, what's the point? Without a good bed, you might as well just sleep on the couch and rent out the bedroom to drifters.