Dier - who netted an injury-time winner to hand Spurs a 1-0 victory over West Ham United on his debut - was born in England but grew up in Portugal and came through the ranks at Sporting Lisbon before his move to North London this summer.
Talking to ITV Sport, the 20-year-old paid particular credit to the Portuguese coaches for allowing youngsters to learn from their mistakes.
He said: "I grew up in a different country and learned a different country's way. It doesn't mean it's better or worse, it's just different.
"It's not really about winning, only once you get to the reserves or the seniors. As kids, you want to win but it wasn't their main ambition.
"Their ambition was just to teach us the best way to play football and let us make mistakes. You were never punished for making a mistake, it was almost seen as a good thing because you learn from it."
Dier has played for England at every level from Under-18 through to Under-21.