One of my own most upvoted questions is Yes/No message box using QMessageBox. In it, I offer absolutely no code, I merely ask how it's done. One of the answerers offers a very nice example.
It's not that I couldn't have figured it out by myself in 5 minutes. But as you can see, the question has 30,000 views, which likely means I replaced 5-10 minutes of trial and error with 20-30 seconds of google search. Multiply it by 30,000, and that's a lot of man-hours.
I posted the question more because I thought that the solution to this should be something that comes up in a Google search in a digested form. It's a common problem, and there's absolutely no reason why tens of thousands of programmers should waste 10-20 minutes of their time figuring it out, each one of them.
By the way, at the time I posted it, the Qt docs didn't actually cover that. There was no "Here's how you make a Yes/No message box". You could figure it out after carefully reading them and piecing it all together, but wouldn't it be better to just be able to find it on the Internet? And also the top google hits didn't offer a ready-made solution. There were either no questions, or no code samples offered, just instructions on how to figure it out on your own.
I just wanted to offer that as a counter-point example that sometimes a question would not benefit from adding code to it.