Usually for me getting a project to 90% complete is the easy part. I can quickly get the core features working in an ugly form. The next 9% takes a little longer.
There are all these little things to add like a usable design, a comment section, notifications. In theory they seem small because they're not the core value or your product but sometimes they're essential for it's success on launch. It takes some time but eventually I get these done.
The last 1% though? The final touches to get ready for launch? Those are the hardest for me.
In the past couple weeks I've finished the last 9% of my next project (Music sharing meets product hunt) but now I'm finding these final touches the hardest to get done. The difficulty for me comes from deciding where to draw the line. Of course the product isn't going to be perfect at launch and there are a ton of things I know need to be added but how do you decide?
It takes some prioritization and self control. And some acceptance that you might miss something that you regret. There's no rush to launch but you also need to be disciplined about so you don't go overboard.
Hopefully I don't miss anything crucial.