Tenure makes a lot of sense for research university positions. Research can take a long time to be fruitful, and many avenues of research won't pan out at all. Tenure helps enable researchers to focus on various problems instead of being stuck to what will have the most payout in the shortest term.
It's never been quite clear to me why tenure makes sense for instructor positions, either at the college or pre-college level. I say this as someone who was a tenured instructor at a community college for a number of years.
It's never been quite clear to me why tenure makes sense for instructor positions, either at the college or pre-college level. I say this as someone who was a tenured instructor at a community college for a number of years.