United forked out more than £70m to sign Sancho from Borussia Dortmund in the summer but he has struggled to find his best form at Old Trafford thus far.
Sancho only scored his goal for United in his 15th appearance for the club against Villarreal in the UEFA Champions League on Tuesday.
"I think people forget these are young men that come in with huge expectations," Yorke, who finished as United's top league goal scorer in 1998-99, told Stats Perform.
"He hasn't had the best of campaigns with England. We've seen that missed penalty, that can have a knock-on effect as well. All those little things, things that young players have to deal with.
"I am a fan; I just probably think it would have been a little bit too early for us to bring him in.
"I think we didn't need Sancho at the point in time with the emergence of Greenwood. I just think that was a position that we didn't really need to go for."
Yorke has no doubts however that Sancho has the quality to succeed with the Red Devils.
"However, you still cannot underestimate the talent the boy does possess," he continued.
"He's definitely one for the future. Again, we have an English product and we want to make sure that we continue to pick up the English players.
"But sometimes that can get a little bit overwhelming at times and people get ahead of themselves a little bit. But there’s no question in my mind that he's a very talented young man and will be a great asset to the football club going forward."
