In summary: extreme levels of RNG.

If an enemy dodges your burst (which happens a lot since the burst takes time), you mess up big time. She's very squishy, which means she needs to dodge more, screwing up her rotation. She needs to be on the field a lot to place her turrets, despite being very squishy, which allows for more chances to get hit and also extends rotations. All this add to a lot of things which can go wrong, leading to frustrating gameplay.

Her damage would be okay if all her burst hits the target, and if she doesn't have to dodge, but the reality is quite simply worse than the theory.

A simple fix of adding i-frames to her skill would do wonders in removing the necessity to dodge, and as such, removing RNG. More HP would also be welcome.

Buffing her damage would not remove the RNG factor, but at least it can make up for it by having satisfying moments of big damage.

She's my favourite character aesthetically, but she's currently benched because there are simply so many better characters that are less frustrating to play: Xiao, Xiangling, Xingqiu, Yelan, Itto, HuTao, Ganyu, Ayaka, Raiden, Ayato, Eula, and Childe despite some being at similar power levels in theory, are much less frustrating to play because there's much less RNG involved.