A decent amount of bank roll, positive mind and luck! put them together and you might end up winning.
Aside from having a strategy, we should have the limit which is very hard to follow or a gambler.
a good timing to stop is the best also.
Yes I agree with you, you must have both a positive mindset, a decent or good bankroll management, setting a stop time to avoid unnecessary loses. Gambling with as little as possible to minimize the risk of losing. Infact all this factor put together will amount to a good strategy of wining than just having a positive mindset. Positive mindset without deploying the following characteristics will result to loses and may probably leed to not wining despite having a positive mindset.