Well, there are two...
One of them is the one I shared in my presentation. So, when the final website should be good enough, that was one of the learnings for me.
When the combination came to me and I checked everything, and they realise that they're not, even if we go live with this website, then I'm going to be successful. So, it's not technically a failure, but it's a failure from their side to understand that it needs to be done beforehand.
But the real, failure is that one website, it's an ecommerce website, and I did an audit for them. It was the worst website that I've ever seen.
They migrated their framework, and then their own react JS right now. So, they didn't have any SEO considerations. They didn't have anybody from the SEO related field for them to help. So basically, they lost everything. They lost most of the traffic and they were huge. So when I was checking them in an archive.org, I was thinking that it was just easier for them to roll back to that version without using the framework than to fix everything, because the content could not be seen by Google. The images, the links are not crawlable at all, and Google sees everything as one page and it cannot equalises all the internal pages to the homepage. So it's a pretty big failure.
Answered by Kristina Azarenko