The primary cause of addiction is the satisfaction you get from repeatedly doing your hobby or an activity. But in gambling, it involves the chance to earn/lose money depending on your luck. Addiction primarily starts in the brain and eventually cascades and evolves into a hobby then to being addicted to such.
I disagree, since also losing triggers addiction. That feeling when you lose in a bet will unexpectedly trigger an adrenaline in hoping to recover your losses which ultimately makes your situation worse. Gambling can never be profitable, let alone beneficial when you view it as a means of earning money.