As computers and networking and the internet and email become more stable, and I think they have done over the years, there is a corresponding expectation that they will always work.
This can mean that when they don’t work people (understandably) try to fix them themselves. Often an unhelpful error message from a bit of software will encourage people to change a password or change some settings.
These changes can cause long-term problems, for instance – changing a password from the right one (but there was a network or non-password issue causing the problem) to the wrong one can cause a permanent error that didn’t exist beforehand. Sometimes the best thing to do is wait. Or, of course, turn it off and turn it on again – which is essentially the same thing (sort of).