Suddenly, you salary is directly related to your boldness and the amount of flack you are willing to take from employees, not your talent or value to the company.
And anyway, money isn't everything. I'd be willing to work for a little less money to have an awesome environment where I am treated well, have good benefits, and do great work I enjoy rather than worked 50 hours a week with micromanagement breathing down my neck stressing me out and doing soul crushing work.
Because you lose people to salary is telling, perhaps your environment isn't actually the best as you imagined, or the salary isn't as fair as you imagined.
However, here's a good summary that argues that pay is actually a very strong motivator, and the discrepancy comes from the fact that saying you aren't motivated by money is considered the socially acceptable response: http://www.utm.edu/staff/mikem/documents/Payasamotivator.pdf
The research about job-seeking behavior is fairly similar, although I can't find the specific sources right now. When surveyed, people say that money isn't the most important thing when they're evaluating job offers, but when asked to compare job offers as bundles of attributes, money ends up being pretty important. Part of the reason is that people under-state how important money is to them, another part is that during the job-evaluation phase, money is concrete, measurable, and knowable, while the other characteristics are very hard to determine.
It's going to sound obvious, but the real answer is that compensation is a piece, but not the only piece, of what people look for in jobs (probably about half).
So if you start with Theory X, for example, "people are lazy and need to be motivated into work through the external means of money and threat of firing", you find plenty of evidence that that is indeed how people function. Anyone who believes otherwise must be mad.
If you start with Theory Y's assumptions, though, "people want to work in jobs where they can be intrinsically self-motivated, and while external factors need to be 'good enough', internal motivation is far more important" - you will find plenty of evidence that this is true as well.
The point is, be very careful of what assumptions you start with, because you might think you can check them with facts, but actually they will shape everything you do and remain largely unquestioned. Therefore, choose your assumptions based on the outcome you want, not based on the assumptions you started with.
After you have alienated an employee to the point they no longer want to be part of their company, why would they say anything other than it was just money? The money is the "it's not you, it's me" excuse. :)
I think when people are polled they feel guilty about how important money is to their job decisions, so they downplay it. I always thought that was odd...its a job. You have it so you can afford to do all the fun things you really want to do. I think millennials are still figuring this out.
I know I've done that before, even at the negotiating table. "I'm sorry, I can't accept this offer. I'm making more than this currently."
I've worked for multiple HR companies who performed studies, all of which showed that salary isn't the highest priority on employee concerns. Yet, in my experience, the number one reason I lose employees (or have left a job) was money.
Also, yes, I have poached employees from competitors by simply finding out how much they were making and offering more. You want to show me how much you are paying your people? It will tell me either that you are not profitable (if you are paying too much) or it will tell me the exact number I need to beat to take your best people.
And rest assured, I WILL take your best people.
Rest assured, I HAVE had my best people taken as well.
Business is not a democracy. Business is a competition. It is a fight for survival. No business is going to be so transparent to reveal enough to help their competitors. Even those 'transparent' companies who post on blogs their entire process? Trust me, they ain't showing you some of the most important stuff. They are marketing to you.
I don't know how this comment will be taken on HN, but I realized some time back that the number of people on HN who are smart is very high, but the number of people who actually run businesses is much, much lower. So I run a company. My comments are based on my experience.