Diego Simeone agreed to extend his contract with Atletico Madrid because the La Liga club ceded to his request that no first-team players be sold this summer.
Simeone, in his sixth full season in charge of Atletico, signed a new deal on Tuesday committing him to Atletico until June 2020.
Atletico could not register new players this summer due to a FIFA transfer ban that does not end until January 2018 and decided to keep their squad from the 2016-17 campaign intact.
"From the time I was told that the club could not sign players, the only thing I asked the club was for no one to leave," Simeone told Atletico's official website. "They made sure of that and that is why we are still together."
Antoine Griezmann, who scored 26 goals and set up 12 more for Atletico in all competitions last season, was a target of Manchester United this summer.
Saul Niguez was also a reported target of United and Barcelona in the last transfer window.
Simeone said: "If I were given a choice of seeing Saul, Griezmann and Koke leave and having a lot of money to sign other players or for no one to leave and not to be able to make any signings, I would choose the latter. They are extraordinary footballers and with them, there is always a possibility of improvement."
Atletico's constant growth over the years was also a contributing factor in Simeone's decision to extend his contract with the club.
As a player, Simeone was part of Atletico's side that won La Liga and the Copa del Rey in 1996.
His return as coach in 2011 began a new era for the club. He led the team to Europa League and Copa del Rey titles before steering them to the La Liga crown in the 2013-14 campaign.
He also guided Atletico on two occasions to the Champions League final, with Real Madrid beating them both times.
"I always saw that this club had a possibility of having enormous improvement and time has proved that right," he said. "I always believed in this club and I always believed that the players that I had could help the club grow.
"We've brought together people that want for the club to improve. As a result, I see players who are older with an enthusiasm as though they were young and the youngsters with an experience they have gotten from the elders. That motivates me, thrills me and we've decided to continue."
Simeone is proud to be the longest-serving active coach in La Liga, with only Arsenal's Arsene Wenger ahead of him among Europe's leading clubs.
"I'm perturbed when someone tells me that being in the same club for many years is complicated," the 47-year-old said. "Why? If the players understand that the responsibility is to play and the coach understands that the only thing is that he has to do is to improve then it's not difficult.
"I'm privileged for the players that I have and the club I'm in. I have more energy now that I've signed the contract extension than when I arrived because I know the club better and I see that the club is growing.
"The biggest push I can give as a coach is to focus every training session as if it were the last. Even though some people may laugh, I always think I could be fired tomorrow."