The referees have to start somewhere. When they are officiating in non-league, the decision whether they are good enough to move into league football is taken on the recommendation of their regional superviser and head of the county referee's association, based on match reports and regular assessments.
Most counties will have monthly meetings and thode who are up to moving up will be discussed.
Each season, a number of refs will be deemed good enough and they will start in League Two. Usually the new refs are not given any big games for some time - this means no key games affecting promotion or relegation, so they start with steady ordinary, routine, mid-table matches, so who do we normally get...those with little or no experience at this level.