I don't understand why my code isn't working

Here is my code. Can somebody help me figure out why this isn't working?

def checkio(words):
    count = 0
    word_list = words.split()
    for word in word_list:
        if word.isalpha():
            count += 1
            if count >= 3:
                return True
        else:
            count = 0
        return False

Thanks!