Mistwell
Crusty Old Meatwad (he/him)
A fighter's attacks always have a chance to fail. High level spells require a spell slot.
So? Just because other classes get diminishing resources and this one isn't a diminishing resource doesn't make them not roughly equal anyway. There is a scale of abilities, from high level of applications with few resources to use them each day, to low application with infinite uses each day. The rogue ability has less application but infinite uses. The fighter gets to use the extra attack every combat encounter, for a potential of a huge amount of damage, but might miss. The spell slot also has the potential for a massive array of applications, but has few uses. This rogue ability is much more limited in situations it can apply to, but is much more reliable in those situations - it tends to just work, as opposed to being highly variable. Still, the comparison is apt - it's roughly the same amount of power in the game and shouldn't be looked on poorly because it's on the high reliability and low application end of the spectrum of abilities.