The highly rated 25-year-old joined the west London club on a four-year contract for a fee in the region of £9 million this summer and is keen to play his part in the Hoops' project under Mark Hughes.
"It wasn't a hard decision to come here," Granero told reporters. "I'm hungry and here I will be able to grow as a player.
"Real Madrid is a great club, I have played there since I was eight. I spent three years in the first team and I will always be thankful to them. But it was time to change and the best way to do that was join QPR.
|17/2||Esteban Granero is 17/2 with Bet365 to score anytime in QPR v Chelsea
"Everyone at the club trusts me and that's all I needed. I know I've made the right decision."
QPR have so far failed to win any of their three Premier League matches, taking just the one point, but Granero has backed his team-mates to show their quality.
"There are a lot of new players here so we must get to know each other first," he added. "We must improve, but this team will do that when it spends more time together.
"One point from the first three games is not unexpected, but this is not the way it will remain.
"This season will be great - I can see that in my team-mates' faces. There are quality players here, so just give us time."
QPR host Chelsea at Loftus Road at the weekend and Granero is fully focused on the game, adding: "Of course it's important to beat Chelsea because it will be our first win and give us a lot of confidence.
"It's great for our supporters because we'll be playing our neighbours in our stadium, so it's about more than just three points. We must train well this week and we will see what happens at the weekend, but we are very focused on the game."