Benchers hold office for life once elected. A bencher can be elected while still a barrister (usually, but not always, King's Counsel in the UK or Senior Counsel in Ireland), in recognition of the contribution that the barrister has made to the life of the Inn or to the law.
Benchers hold office for life after being elected. A bencher is selected as a member of the bar association based on their contribution to the Inn or the law.