[mrmaximus]

This guy is just trying to tout his own product. That aside, Kaggle can be quite useful for learning... at least it used to be. Kaggle got me into machine learning 2-3 years ago and now it is about 50% of my job in consulting. Problem is, Kaggle is running too many deep learning, image based comps and they are lucky to get a couple hundred competitors each. The wider user base engages much more heavily in transaction based competitions, and these are much closer to the real world problems you are likely to encounter as a professional.