Question: I seem to be repeatedly stuck in a situation where release dates are set not based on anything technical, but because someone in Sales has committed to a customer by then. Based on discussions with friends in development at other companies, the same thing seems to happen.

"Here is the committed feature set and here is the committed release date", and it's difficult to argue because at this point there is money riding on it, and that trumps everything. 

**In general, is there a way to push back on this?** If not for this release, what about in future? The problem I have is that the only way I see one way of doing so, and that's by doing the best I can, but release the software 'as is', so to speak.

I don't want to release bug-ridden software since it's my name attached, but doing 80 hour weeks for months at a time just vindicates the arbitrarily set release date.

edit: for the record, I'm not doing 80 hour weeks now, just that comes to mind as what would be required to cover the expected feature set by the release date.

Answer: 
This is almost a universal thing in smaller companies as they have a greater need to close a deal. Until I was brought into sales meetings at my company I was bitter about this but I can at least understand how and why it happens a little more.

Clients want it fast and many will play hard to get. This encourages sales to bend on time commitments just to get something signed. A signed contract is gold because you can acquire capital or credit using one. Sometimes it is better to have a tight deadline than nothing to work on at all.

Other times if it is a hot market and there are a lot of competitors then the company has an impending need to get a product out the door FASTER than everybody else. A bigger company or one with more capital can always hire more resources, a smaller one can't.

Where it is scummy is when the deadlines are truly artificial and it is pushed by sales and management to secure large bonuses for themselves.

Don't make a habit of working more than 45 hours a week, it is bad for your health and that comes first.
No

I tried to make this a two letter answer and the stack wouldn't let me ... but the answer is 

No

Which, isn't completely true if you own / run the company, of course. If you're in *that* position you can drag the sales team in by the ears and "have the talk". If, however and as I suspect, you are just a "lowly" technical person your only recourse is to complain "UP" the chain of command. That being said, my experience has been that in companies where this happens, management is aware of situation and doesn't care.