Getting tenure in many academic institutions is very stressful, as requirements are high, and often higher than for those who obtained tenure before and decide on one's fate. It should thus not be a surprise that some people crack, in one case unfortunately leading to a shooting spree yesterday.
But is tenure really worth all this stress? Tenure decisions too frequently lead to internal strife, and someone who has finally obtained tenure after a long battle and appeals ends up leaving anyway most of the time because relationships with colleagues are strained. And even in clear-cut tenure cases, tenure is not Nirvana. Take this nice presentation of myths about tenure from the National Education Association. In short, tenure does not guarantees a lifetime job. It only gives a right to due process. And there are plenty of ways to make a tenured professor feel the consequences of under-performance. Also, it appears that on average tenured faculty teach and publish more than untenured ones. And academic freedom is not much different whether one is tenured or not.
Tenure is not what it is advertised to be. With tenure, one is virtually locked in place, as other institutions would not hire you without tenure, and hiring with tenure is a huge deal and thus much less likely. Being unhappy with tenure is worse than unhappy without tenure in some cases, as mobility is higher in the latter.
In my case, I wished tenure were not an option. I do not need tenure as a motivation to teach well and do good research. I am sufficiently interested to continue doing so after getting tenure. Tenure does not change anything. I am not interested in promotion, as it really mans taking on responsibilities that I can do without, like sitting on useless committees. Just evaluate me, reward me and punish me according to my performance. And if I am not happy about how I am treated, just let me test the market without having to force my tenure on other institutions.