Keep a list of your mistakes so they never happen twice & you’re on your way to developing standards.
I’ve created various checklists based on over 10 years of web content management work & taking into account other standards from Government & the world wide web consortium.
It’s quite reasonable to make decisions about what standards you aspire to meet with your site, based on business needs. But don’t leave boxes unchecked by accident.
From W3C accessibility guidelines, including colour contrasts, alt tags, labels, text alternatives & more, to checking http status codes, duplicate content or page title issues & other search engine friendly standards, I can help make sure your site ticks every box.