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I feel like I'm pointing out the glaringly obvious, but many people actually want to make their institution a better place, design policies that benefit future students and colleagues, etc.

A benefit not mentioned in the other answers is a reduced teaching load in many universities. Possibly zero teaching load. If someone does not like teaching, but likes (or has a lesser dislike of) administration and research, then the reduced teaching is a motive to become an administrator.

Oftentimes, these administrative positions are only temporary and after a while, professors having such positions will become regular professors again.

This means that they can (1) work on improving their department, (2) perhaps get a higher salary for some time, (3) get reduced teaching load, and (4) help to grow their professional network within the university, all while having the assurance that the job that they actually like to do (Professor) for will be waiting for them when they don't want the higher responsibilities any more (or are not re-elected to these positions).

This is something that you can't get by switching to a job outside of academia -- once you are out of academia for a few years, it's quite difficult to get a good academic position as your scientific output is normally lower (or insignificant) when working for a company (perhaps with a few exceptions). Hence, you won't be such an attractive candidate (again, with exceptions).

One factor I don't see mentioned in other answers: pensions. In one school I'm familiar with, your pension is 75% of your salary averaged over your five best years. So if you are department chair or dean near the end of your career (as is usually the case), you get the ~40% bump not only for those 3-5 years, but effectively for the rest of your life. Particularly since the increased administrative load may be partially offset by a reduced teaching load, this is not a bad deal.

Echoing the other answer: some people do see the opportunity to better their university. Also, in my experience, some people decide that, even though they did well-enough in research-and-teaching to get tenure, etc., that this is not their genuine strength. So, having considerable understanding of both research and teaching, they are uniquely qualified to try to administer things related to that. We rarely hire "professional managers" in academe, because we do not trust that they know what is going on here.

Why do people want to be professor? They do less direct research (compared to post-docs or full time researchers) but instead they let other people execute their ideas. If you become head of department or a whole university, you can "steer" a lot more people but you become more indirect.

It is similar to why people climb the hierarchical ladder in industry. They loose contact with the real work but their thinking influences more people.

A few more aspects of motivation I have not yet heard mentioned are:

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  Salary. In many universities, senior administrative positions offer a salary increase over the (often uniform) salary grade of a professor. For most people this is a secondary motivation, and Professors' salaries are not that low to begin with, but it does carry some weight.


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  Prestige. It makes many people feel more accomplished to have reached higher positions or ranks; to be more in the public eye; to speak for their departments or universities in various circumstances. Some might consider this vanity (and there are certainly vain people in such positions at times), but social recognition does motivate most people at least to some extent.


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  Getting away from research. Paradoxical, isn't it? Well, some Professors are not as motivated as they used to be. Or - dislike the current fashions in their field. Or have just evolved as people and want to try something different in life, without quitting their job. An administrative position is a way of doing that instead of focusing mostly on your research.

Having said that - I agree with @RaghuParthasarathy's answer, that the primary motivation is hopefully the wish to actually do right by your institute or department.

Here at the college I work for, our state retirement system (FRS, florida) administrative positions above a certain level accrue retirement pay at 3% per year vs. 2% per year for us peons. Additionally, retirement pay is based on the average of the highest 3 years of earnings from any FRS employer. Rather common for admin types to teach a few classes as adjunct or run for city/county political positions, or to teach overloads, etc. all as a way to crank that retirement paycheck up as high as you can get it.

Our administration also pull faculty away from the classroom (we aren't a research institution) to work on special projects like our SACS accreditation, etc. though this is usually time limited (1-5 years) with a promise of returning to the classroom and no loss of tenure, etc.

So from here at a "junior college" type place, it is about that retirement pay.

The difference between "administration" and "teaching" in a university is like the difference between the managerial and technical tracks in a corporation.

The "average" university person probably wants to remain on the "technical" or "professor" track, but some people will prefer administrative duties, and a chance to exert executive power, either inside or outside the university.

As a child, I didn't want to be a movie star, but I did want to be a "producer," which would have made me their boss. That was true even though I knew that the stars made more money.

In systems where internal appointment of academic management still exists some staff members who are collegial or union will put themselves forward in order to prevent the filling of the role by an unknown external, an uncollegial peer, a non-union worker, or a yellow dog or scab.

To the extent that the academic management role has some freedom of action they may be able to protect their unit from higher levels of management for a period of time.

This perspective assumes a higher level of proletarianisation, class conflict and class consciousness amongst academics in a unit; but, I have seen the case in the Australian system. Sometime everyone else steps backwards faster when colleagues ask for a volunteer.