Here we go again ...

OHBOY

This exclamation might follow a frustrating repeat of the same mistake or when facing an all-too-familiar problem. Think of a casual, four-letter phrase often said with a sigh.

Here we go again ..." is a phrase often said with a sigh when something frustrating or repetitive happens. The answer "OHBOY" captures that exasperated tone—it’s a casual exclamation (like "oh boy, not this again") that fits the clue’s weary vibe. The ellipsis in the clue hints at trailing off in annoyance, which matches the informal, slightly dramatic feel of "OHBOY.