Under what circumstances would a girl suddenly begin doing make up?

Let's say we’re talking about a girl in the 20s and never use make ups before. And then suddenly she started having a large interest in make up, hoarding tons of piles of it and trying a different look all the time, sometimes in the same day, in her own room.

Is this most likely due to a guy she likes has given her hope? Or some other reasons involving a guy?

It's not like she didn't knew make up existed before…

---

Answer:
Well mostly, girls would wear make up under these reasons
~someone insulted the girl, damaging her confidence
~She wants to feel sexy
~She feels odd
~She has pimples
~She thinks she's predictable
~She wants a guy

---

Answer:
sounds like someone (with terrible grammar) is jealoussssssssssss

it could be but it doesnt have to be. maybe she just wants to begin looking like a more put together woman. maybe she wants to begin looking like a woman instead of a little girl, and she thinks that make up can help her accomplish that.

---

Answer:
Maybe she is starting to get a bit insecure or just wants to try out new ideas with make up. It could also be that she wants to impress a guy