Without tenure faculty members would be hired on term contracts. The importance of tenure is emphasized by considering the nature of academic units in colleges and universities. Such units are not businesses and that they cannot be run as such. The variety of course and research topics pursued by faculty members in a typical academic department is so large that it is impossible for one human being to master, let alone direct. The better model of an academic department is a community of responsible members.
Successful communities grant their members certain rights.
Tenure is also important in the educational process. We learn by juxtaposing and questioning ideas. If faculty members are at risk for discussing unpopular ideas in the classroom, such as evolution when a governing board is populated by individuals who do not believe in it, they cannot provide a quality education. In my opinion, tenure is receiving a lot of attention today because it is generally believed that the high cost of a university education is due to an expensive professoriate. Regardless of what salaries are paid to faculty, they are not the cause of high tuitions.