I prefer to write about things I know and usually I do. Those are the hubs of mine that wind up getting the most views because hey, I actually know what I'm talking about. Whenever I do research and write hubs on topics I know little about, I go through them several times before I hit publish because I want to make sure I've grasped the concept. I wind up spending days on those hubs instead of hours like others. What I write today can be seen through fresh eyes tomorrow and for the next three days. I can also find holes in whatever I've written or things that need to be tidied up or better explained.
I know my hub will be great if I'm already writing down where I can submit it to and know that it will receive several hundred views. If I feel right about it when I'm writing it, before even giving it a second glance, then I'm not worried about how its going to do. Hubs don't always do amazing the second you publish them. Someone once said that they are an investment. If I feel good about my investment, if I think its going to be a sound investment, then I publish.
You can always go back and edit old hubs and make them better and/or update them. If I think something is good now and then find out a few weeks down the line that I can make it better, then I will.