The Spaniard was speaking after seeing four of City's under 21 crop swap the Etihad Stadium for St. Mary's this summer with two securing deadline day moves.
Republic of Ireland goalkeeper Gavin Bazunu (20) and midfielder Romeo Lavia (18), made switches to the south coast earlier this summer.
They were joined by 19-year-old winger Samuel Edozie and 18-year-old left-back Juan Larios who secured five-year deals with the Saints, late on Thursday evening.
The impact has been immediate for the former City youngsters with Bazunu having started all five of Southampton's Premier league games so far this season and Lavia scoring in Tuesday night's 2-1 win over Chelsea.
Edozie and Larios are next to try to force their way into Ralph Hasenhuttl's starting eleven and Guardiola spoke highly of the young players that have jumped ship in search of first-team football.
The City boss also mentioned Joe Shields, who left Manchester City's academy to become Southampton's new head of senior recruitment this summer.
"A big compliment for the club to educate them and bring them to the Premier League. Southampton is an incredible place, the guy there [Shields] was working here, he knows them really well. We wish them all the best," Guardiola told reporters.
"All of them are fantastic players. Southampton bought really good players. We know the academy are so proud.
"The incredible job they do. We rely on them a lot, but at the same time, they have offers and patience doesn't exist.
Guardiola revealed that despite the cluster of young stars moving to St Mary's this summer, City have buy-back clauses in the event they blow up into future stars.
The Manchester City manager said: "They could stay one or two years. EDS [Elite Development Squad] competition is so light, it's not real competition. They want Premier League football, so after agreement with the clubs, we have buy-backs in case they explode and we can get them back."