To properly debug a system, you need a reasonable hypothesis that explains how the system got into the failed state, preferably one that you can reproduce, so that you can fix the bug. To debug a team, you also want to look for a hypothesis around why the team is having problems. Do this in as minimally invasive a way as possible, to prevent your meddling from obscuring the problems. As an added challenge, team problems are not generally single failures but are more like performance issues. The system is running, but it seems to slow down from time to time; the machines are OK, except occasionally they crash; people seem happy, but attrition is too high.