Employers favor people getting things done in a professional way. I have colleagues who stay in office 20% more than i do (10h instead of 8h), yet they produce less code and much less *well working not completely bugged code*. Planning my work and dissecting a problem into small, doable (and commitable) tasks came to me with age and experience. If a release date comes close, it gets even more important to think twice before you type and avoid stupid mistakes - and thus, my experience shows: avoid stupid all-nighters or 100h/week coding marathons. A missing feature usually can be explained and added later. But if a fucking show-stopper bug causes an undetected gross miscalulation, then things escalate quickly and nastily, up to loosing the customer.
I had the case that some moronic project leader did not honour the feature freeze, but forced a junior colleague of mine (he knew I would not follow his order in that) to patch something in the middle of the code on the last afternoon before the review meeting (wihtout telling the rest of the team). He did not even put the time into looking into the new pdf report generated by the program and sent it directly to the customer as a demonstration. I can tell you, the customer was impressed that we presented software the output of which were not inspected by a human a single time (Reported cost error was by a factor of 10^12).