Amorim has attacked United's academy talent this week, branding them "entitled".
Asked about his approach to the club's youth traditions, Ferguson recalled to the Press Box: "I think my appetite was for young people and players.
"When I went to St Mirren, they had no money. The best thing I could do was sit at the coaching schools on Tuesdays and Thursdays with the young players, and then five ended up becoming internationals.
"Then I went to Aberdeen and continued that ethic; we won the European Cup without our own training ground and eight players were produced by the club. It was fantastic.
"When I went to United, Bobby Charlton was in the meeting and I said: 'I don’t know why you have appointed me unless you give me the reign to produce young players.' Bobby said, 'That’s done, you’ve got the job.' Bobby Charlton was a fantastic man."