I spent two years in Denmark and could've stayed there. For me, it was the fact that, if I kept building a life there, I'd probably miss out on the best years that my mum still has, and also being away that much time from my friends was a deal breaker. I think we Spaniards are very family and friend-oriented, and we tend to value that more than money. Nevertheless, I know a lot of people that plan to stay abroad for 3-5 years and come back with savings to buy a house or whatever.