The real problem is when you have someone who is just competent enough to deliver mostly-working bit terrible code. Which the rest of the team has to maintain.
If the person is fresh out of college, of course, this is understandable and a senior person will likely be mentoring them, and reviewing their code. But when you have two such people who gravitate to reviewing each other's code, you have a serious problem that may not be immediately apparent.
If the person is fresh out of college, of course, this is understandable and a senior person will likely be mentoring them, and reviewing their code. But when you have two such people who gravitate to reviewing each other's code, you have a serious problem that may not be immediately apparent.