Most of the time in gambling you are losing probably, i don't see any good effects from gambling, except having fun when you are winning, with losing there are many bad effects like, you can get depressed by losing a lot of money, its easy to get addicted to gambling so you can make problems to your family by getting money from them, i had one friend doing this but he is okay now .
This is why most advises not to be addicted in gambling. Because it has good and bad effects indeed, once you cannot control in playing addiction is sometimes hard to control. Those effects above are true once we become addicted in playing gambling.