Generally there are several tiers: small projects
Your NDA is a Copy and Paste Job
Nondisclosure agreements are often copy-and-paste jobs that say the same thing. Even if you had your NDA professionally written, consider the fact that your attorney or paralegal most likely gave you the same document that they’ve given another client only with your name on it. In fact, they’d be a fool not to do it that way. Why should they write the same thing twice?
Now, that being said, as a developer, I often reuse code from other projects. While the finished project never looks the same, some of the same code gets used on multiple projects. In fact, that’s why frameworks exist all over the place. Code reuse does not mean that I’m selling your idea to other people, nor does it mean that I’m selling you the same product as someone else. It simply means that, like your attorney or paralegal who wrote your NDA, I too wish to save time by not writing the same thing twice. You also save money that way.
Your NDA would rob me of my ability to write even a single line of code the same way in two different projects. Heck in some cases you don’t even have to prove that I stole your idea. You could just have me sign an NDA with a proper provision, take me to court claiming that I stole your idea, and get paid as much money as that NDA afforded you for that situation. Happens.