This is more of a reminder than anything else. I have posted similar items in the past but it bears repeating every now and again. I see entrepreneurs so often drop the ball when it comes to time and momentum. What I mean is that so often momentum is lost because people simply take too much time. A sense of urgency is always necessary. Getting bogged down in analysis ("analysis paralysis") is oftentimes your worst enemy. Always remember that momentum is on your side when it comes to financing rounds and general day-to-day with VC's.
As a VC, I tend to like positive momentum. If a deal "feels good", things "fall into place" and deadlines are kept, psychologically I'm more involved. If you tie me up in endless negotiation, try to optimize every last detail of a deal or decision and basically take the wind out of the deal's sails, my mind tends to drift. Further, if you keep stalling in the hopes of a better deal coming along, I tend to catch on to this. Don't forget, we do this business every day and most of us have seen it all. There's always another deal to move on to.
If you sense that a firm generally likes your deal, has committed time and effort into getting a deal done and you generally are comfortable with it, keep the momentum going. Get things done and close the deal. Nothing is ever perfect nor can you continually optimize everything that comes along. Yes, you may make mistakes and I stress that you avoid the big ones if possible. Sometimes you do have to slow down to check the details. Yet little mistakes here and there sometimes just don't matter in the grand scheme of things. Certain terms don't much matter if you've spent every last dime. 10% more of an insolvent company just ain't worth much! Keep up momentum.
Update: Mark did a great post on this with lots more detail. Check it out!