I can't say that I'm affected by this sort of thing to the same extent that you are, but the feeling of 'suddenly losing interest after gaining understanding' is easy to relate to. I have no problem keeping focus for hours trying to understand how a particular bug could possibly be happening, continuing to work after hours until I figure it out. When I'm still in that 'learning / understanding' phase, there's no effort required. I want to know what's going on here and it will bug me until I get it. And hopefully, the end solution is a couple line fix.

And very often, it is. But sometimes it ends up being the type of problem that requires a much more involved architecture change to solve correctly. It's not just a one line change, but something the whole team will have to sign off on. Which will require at _least_ 100 times the work of the usual two line fix. By this point, I already 'know' how to solve the problem, and it could be very easy to lose interest. But the error emails keep on coming. And they're easy to ignore because "they're just those weird errors we get from that 3rd party API we use so there's nothing we can do about it."

But these emails are really annoying. So I find I have to reframe the problems from understanding how to fix the issue to how to get buy in and get the fix actually deployed, and I haven't run out of these types of problems at any company I've worked at, and that works for me to keep my attention.