One of the most stupid phrases I hear again and again is "to not reinvent the wheel". Guess what, if no one had ever dared to take the first iteration of something, throw it out the window and start from scratch, we'd still be living in the stone age. If you're gonna use a library or a framework, fine, that's totally valid. Just make sure to actually understand the tools and code you're working on. People now tend to use these without knowing exactly what they do. And then once the original authors retire, no one knows what to do if something breaks. There can't be innovation if you don't try to reinvent. Don't shy away from writing from scratch sometimes.