[bvirb]

If you can afford to and you have a team dynamic where "everyone makes mistakes" you can give them more responsibility -- like other people being stuck until they actually fix the build. But that can backfire if they're very junior or the culture is very negative around making mistakes.

Otherwise asking them questions can help. Come from the place that you must be missing something and ask them why you can't get XYZ to work as expected. Make them figure out what the problem is. Really get in the mindset that you're missing something though, or it can come off as patronizing.