The biggest mistake that people make when they try to pressure wash anything under the sun is that they attempt to rush things at this current point in time. While we can understand that you might not have a whole lot of free hours on hand due to your demanding job as well as familial responsibilities, suffice it to say that trying to rush through a pressure washing job will result in you really regretting the decisions that you have managed to make so far without a shadow of a doubt.
A common byproduct of people trying to power wash without giving it its due amount of dedication is that their wooden structures begin to collapse. The best case scenario that can occur in this respect is that your wood will be too wet to apply a staining layer on top of it. Moisture within the wood that will seep in during a pressure wash will stay there for a couple of days, slowly working its way out of the wood over the next few hours which can result in a weeping appearance in the wood stain.
As a result of the fact that this is the case, you should wait the aforementioned duration before staining your wooden deck. Decks need to look good because they are meant for more than just straight up functionality, and staining the deck is an important aspect of that. Hence, it stands to reason that waiting for the deck to properly dry would fall within the category of your best interests. Being hasty about the post pressure wash requirements is never a good idea no matter what people say.