In a well run parish all volunteers would serve 3 year rotations, then be asked to step aside for new people to come forward to serve. This would eliminate one of the major problems in parishes - ownership of ministries, i.e. one couple “owns” the 9:00 Mass choir, the same 3 couples are “always” lectors at 10:30, so new volunteers never get a chance, the leadership of parish council bumping among 2-3 people. If the pastoral leaders do not remove catechists who are not doing the job, they are blocking the action of the Holy Spirit who is calling new people.
what helps me is that I am “not from here” which means I am not emotionally tied to the parish and the people, I can be much more clear headed about recruiting, evaluating and firing volunteers.