Where is her luck ( ´,_ゝ`)

It’s so hit and miss Like you’re telling me she can knock a guy half conscious from a door, but can’t avoid getting held hostage?

Her ability has a massive consequences of getting bad luck. That's why she can't use it all the time. Whenever she uses her good luck, a bad luck is surely to happen in order to compensate her using good luck. Well that's so far how I understood.