Why are people so opposed to reinventing the wheel? In a professional context, I understand[1], but this is a personal project someone wrote to scratch their o

Why are people so opposed to reinventing the wheel? In a professional context, I understand[1], but this is a personal project someone wrote to scratch their own itch. Why is it unjustifiable? I can think of plenty of reasons to reimplement something but I think the burden is really on you to say why it shouldn't be done. If you think replace is a waste of time just don't use it - simple as that. [1] I've spent the last two years maintaining an application written in a homegrown web framework - don't get me started.