Struggling with a bug for hours and junior fixing it in an instant in front of me

You saw what you expected to see, not what actually was there. It is a common problem of authors, engineers, coders... everyone who works creatively but creates stuff that has to follow some rules.

There is nly one solution to that:
Interrupt debugging with some other mentally demanding task to clear your natural neuronal network's internal assumptions about the code.

@Oktokolo was that a "clear the cache" analogy 😅

But your right, if you stare at a problem long enough you won't fond it, sometimes the best solution is to work on something else or bring in a fresh set of eyes.

hah, i was in the position of that junior a few times. it's always a struggle to decide "okay, i'm gonna chime in even it's going to make the senior angry/deppressed/whatever" :)

They'd be more than happy to help. They'd feel like they have finally worn the "grown up pants" now. 😛

... And they would totally panic if they got it completely wrong, so they have that insecurity too.

@C0D4
Yes, it is.

@rutee07 is bang on, but to add - bring a senior isn't about solving things faster / better etc. than juniors. It's about the experience required to spot bad "solutions" before they become an issue, make long lasting and positive high level design decisions to drive a project forward, make helpful suggestions about the many different ways a problem might be solved, etc.

If it was just about being able to do everything better than the juniors, most seniors would lose their title very quickly, myself included.