The main aim of signing Ronaldo for Juventus was clearly to win the Champions league, which they didn’t achieve. I see this as the main reason why people claim Ronaldo wasn’t a good signing for Juventus. As well as him being one of the main reasons for Juventus’ economic issues.
It was not. The goal was to win UCL. Juventus were UCL finalists a few times the years before he arrived. He was supposed to get them over the line.