This is more complex than you might initially expect. The early cars from Tesla historically have been problematic. This certainly includes Model 3. People with the early VIN's are at much higher risk of experiencing issues. Tesla most certainly does make constant changes that typically resolve the known issues over time. At this point, current production appears to be at least average reliability if not better. They are most assuredly not the most reliable vehicles ever made, but a great deal of people have no troubles, my self and my brother included. The truth is cars break, and Tesla being a newer car company isn't immune to fault. I'm a picky individual, and I still think the Model 3/Y is the best daily driver money can buy, all things included.
A great deal of the people complaining about the vehicle are complain about perceived lack of initial build quality, customer service, lack of understanding the vehicle and its intended operation, and not really actual reliability concerns that result in the vehicle not being able to move. Lots of people hold Tesla to a much higher standard than other brands, and a lot of buyers are first time new car buyers, or buying far above the normal price range they typically shop. This means a great deal of buyers are exceptionally picky and can be unreasonable at times, demanding perfection. The car is not perfect, and Tesla certainly occasionally does some unsavory stuff. Overall, it's still absolutely terrific and worth it for the overwhelming majority. If you can tolerate the potability of a minor blemish in a new car, value the performance, and don't drive cross country straight every weekend, Model 3 is absolutely a tremendous vehicle.
