The tank sits close through the chest, shoulders, and torso without turning into compression gear. Higher arm openings and wider shoulder straps are cut to sit up on the lats — marketing language, but in practice the cut is more flattering than a basic ribbed tank.
The flip side: it will show your body, waist included. That is the design working as intended, so if you want coverage rather than shape, this is the wrong cut no matter what size you order.
Wash behavior is where sizing decisions usually die, and it is the reason these earned drawer space: washed cold and tumble-dried low, the fabric kept snapping back where the cheaper Amazon tanks I compared against stretched out and lost structure. Sizing choices survive the laundry.