Spurs beat relegated Sheffield United 3-0 at Bramall Lane to cement fifth place and qualify for the Europa League but they will be left to wonder what could have been after they had topped the table earlier this season.
Australian Postecoglou also questioned the club's mentality earlier this week when they failed to clinch Champions League qualification, saying their foundations were 'fragile' but praised the effort from his side to finish on a high.
"Contrary to my general demeanour, I have loved every minute of it. It is a great challenge in the Premier League and taking over a big club that didn't have a great year last year," Postecoglou told reporters.
Spurs slumped to an eighth-placed finish last term and missed out on European football.
"You understand it is not going to run smoothly. I have enjoyed the whole season. I have got some lofty ambitions for the football club and until we reach that point I am not going to be smiling too much.
"Any manager wants maximum effort and I have got that from everyone involved. I have enjoyed it and am looking forward to pushing on from here."
Postecoglou had replaced Antonio Conte after the Italian was sacked following similar complaints about the team's mentality last year but the Greek-born Australian quickly became a fan-favourite with a blistering start to the season.
Spurs lost striker and top scorer Harry Kane to Bayern Munich but went the first 10 games without defeat as Postecoglou won the Manager of the Month award three times in a row.
"It's been good, it's been eventful, it's had a bit of everything. I am obviously not delighted with the way we finished the season," he said.
"But in fairness to the players and staff, we have been in the top five all season in a year where there was a fair bit of upheaval.
"We finished eighth last year, player turnover, different football, different way of training - it is not easy to maintain a level when you are trying to do that."
