make good things, shouldn't be based on a sole person's opinion i suppose. I didn't want to elaborate on what that is, but as you pointed out, use standards and conventions, well documented and tested libraries. Don't stray from the common thing if it's not needed. Reason about data first, then code. - these are all common advices too, easy to find if you look on any search engine how to build something 'good' or 'properly'. or 'how to program professionally'. - i'd hope someone uses the resources and knowledge available to them that others have spent a lot of time documenting and building.

That being said, its not always the case and you are right, 'make something good' is a bad advice, essentially it's not advice at all.

I would say as advice - don't do something alone if you want others to use it. Try to get feedback as early as possible from people you trust, and from people you'd expect to be your consumers/users. And always listen to that advice, don't throw it into the wind. I think that's the best advice if you want to make something 'successful', because the label of successful ultimately will be granted to your product by your users, not yourself.

Sorry to put a 'bad advice' if it was taken as advice :-). I don't mean to make bad things even in advice ^^.