Reusable code is usually pulled out into a library and reused that way, rather than copied and pasted into a new project. You might copy and paste some boilerplate to new projects but it wouldn’t be anywhere near 25% of the code.
I’m not sure why someone downvoted you (it wasn’t me!) because your comment did seem like a genuine question.
/cdn.vox-cdn.com/uploads/chorus_asset/file/24016888/STK093_Google_01.jpg)
Reusable code is usually pulled out into a library and reused that way, rather than copied and pasted into a new project. You might copy and paste some boilerplate to new projects but it wouldn’t be anywhere near 25% of the code.
I’m not sure why someone downvoted you (it wasn’t me!) because your comment did seem like a genuine question.