Getting a project going is the most important part, then you can make any necessary changes or tweaks once you have got started.
Remember that you don’t have to get it right first time, you just have to get started.
I’m not saying that you should settle for rubbish. Just get it out there as soon as it is good enough. You can always improve it later.
What happens if there are problems? The good news is that your customers will tell you! This is the best way to know which changes need making first to get it right.
So in summary, don’t wait for perfection. Get started now. There is no time like the present!