Time can work for you and against you. Working in short production loops means you need to focus your efforts and prioritize the features that are essential to whatever it is you’re making. It’s amazing what you can produce in a short period when you know what you want to prove and have a game plan. With some practice it's easy to estimate how much work you can get done in a short period, say, a day or a week. Extend that deadline and it becomes harder to imagine how much work you can get done. The questions pile up, the goals become fuzzier, and there’s more room for distractions.
The longer deadline, however, gives you more time to reflect on your product, make adjustments and add the polish that transforms a good idea into something great. What to do? Break longer projects down into smaller production cycles of features, goals or stages of production. Know what you want to prove for each of these and take time between cycles to reflect on what you made.