Well, Clover has never really liked tight or restricting clothing. She is a very active person, walking, running, rollerblading, ect ect. So tight/restricting clothing always has made her uncomfortable and feel like she doesn't have a full range of motion. So long as the item is safe to wear while doing the activities she is doing and doesn't restrict her movement she'd wear it. For example tight clothing like sports bras or shorts don't restrict her, but say some skirts or dresses wouldn't be safe to wear while say rollerblading, so she wouldn't wear it.

When she became pregnant and rather large around the middle, feeling things tight on her belly restricting her already more restricted movement and life. Just made her feel HELLA uncomfortable. So crop tops, looser tank tops and shorts became her bread and butter. Not to mention stealing some of Jack's clothing too since it's nice and loose on her smaller frame.