Dishonesty on Teacher Evaluations a Serious Issue

According to a study authored by a pair of marketing professors, students are prone to stretching the truth on teacher evaluations.
About a third of the students surveyed admitted to stretching the truth at one point, and 20% said they lied in the comments section. While some did it to make teachers they liked look good, a majority did it to punish those they didn’t like.
As a former adjunct professor, this is an issue that concerns me a lot, so I’d really like to understand what’s going on with this lying. Feel free to leave your thoughts in the comment section and I will respond to them.
First, I’ll address the main issue: Especially for adjuncts and part-time professors, teaching evaluations are the main way we’re evaluated by our superiors. A bunch of bad evaluations means we won’t keep our jobs.

Now, I’m not against giving bad professors bad evaluations, but giving a good professor one just because you don’t like them? Are you really comfortable costing a qualified person their job by lying? Would you be happy if in your first job, the people you worked with who didn’t like you lied to your boss and got you fired?
But a much more interesting piece of the article states that a Duke study found that professors who give better grades get better evaluations. And, to me, this is the real danger.
Creating a culture where good grades are rewarded with good evaluations, or students give bad evaluations to teachers they dislike will result in one thing: Professors more interested in currying your favor and giving you an A than challenging you. While that may make your class more fun, and give your GPA a nice boost, you’re not learning anything in the process. That’s going to hurt you down the road, as you’ll be ill-prepared for future challenges. It doesn’t help the professor either, who doesn’t get the feedback they need to improve.
Teaching evaluations aren’t perfect–and that’s a whole other issue–but for a lot of faculty, they’re necessary. If you’re filling them out, you’ve got a responsibility to do so fairly.