Errors happen, I know that every time I write an article and someone corrects me. Unlike my grammatical mistakes, plan errors as a 401(k) plan sponsor can hurt you in the pocketbook. The problem with some of these errors is that they can easily be avoided through a little diligence on your part. Routine mistakes are more frequent than catastrophic ones, they can be early be avoided. This article is about the routine error you should avoid making.