No winter break, more domestic cups, domestic cups have a higher profile, etc. Premier League is played at a higher tempo under harsher conditions. The wind breaks most people who arrive straight from the south european leagues, which is why they need that long adaptation period. It's not like any of this is a secret. When you put it all together it means that players (and thus teams) tend to break more frequently.
I happen to think La Liga is stronger than Premier League, but the difference is marginal when you exclude the two big elephants in the room. English clubs would have a lot more European success if they weren't held back by their own FA. There seems to be this disdain for European football in England. I'm not sure if it ties into the general disdain for the rest of Europe, but English clubs aren't given the best chance to succeed in Champions League. How many times have we played an away game in Europe on a Wednesday night only to be scheduled for a league game at noon on Saturday?
