I think this is the definition that people are using when they don't want to use the word "problem"
issue
an important question that is in dispute and must be settled; "the issue could be settled by requiring public education for everyone"; "politicians never discuss the real issues"
I think people use "issues" when they want to bring something to someones attention without using an emotion-laden word like "problems". Saying someone has "issues" is kinder than saying someone has "problems", I guess. Probably due to the way we think of problems as being unsolvable, whereas issues have answers. No one likes to admit they have problems, so we have issues instead. In my mind, a problem is something that needs solved, like a math problem. An issue is something that needs to be dealt with somehow even if you don't really solve anything. (can you tell I work for the government?
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