Is English an easy language to learn?

I'm a native speaker, but I love learning languages. I've always wondered what the hardest things are for people who aren't native English speakers. Whether it be certain accents, words, phrases that don't make sense, etc. So ESL Learners, what's the most difficult thing about English for you? How did you all learn to speak English so perfectly? I would think that 95% of you guys are native English speakers by the way that you write. What's more surprising is that some of you come from countries in which I've heard most of the population speaks little to no English, so I'm very curious as to how you all learned it so well. I was mostly just asking out of curiosity because the few people I know who speak more than one language either learned it when they were young from family or learned it on their own later on because U.S. schools don't do a good job with foreign languages.