The casino is giving you an option to select between the two faces. It is either you wait for the overall result before you cashout or you will have to take the little winning while forfeiting the rest without bothering about the overall outcome. The cashout option has made many gamblers to make little profits avoiding a total loses, while also had been a bug regret to others that choose to cashout without knowing that the overall result will fall to there prediction. This is a test option and we always have to scrutinize every game we have bet on before taking any silly decisions that will make us lose totally.
I think those who bet with money that they can afford to lose will barely use this option because they usually think that even if they lose, it's not a problem, so they don't resort to cashing out before the game ends only to get a portion of the profits they have been anticipating to get. If I have made a bet of say, $20. I know I can afford to lose it, so if I'm getting an opportunity to cash out $30, however, the end result could get me more than $40, I wouldn't go for it because I'm already ready to take the risk.
Some people don't think this way and that is because they don't want to lose the money they have bet probably because they can't afford to do it. They do take the risk of making the bet, but they feel they should take whatever they are getting instead of taking the risk and becoming greedy.
I think that even those with disposable income will take profits from time to time if they can make more than they lose (obvious) and if they have structured plans and a reason to gamble
Those who are lost on the thrill and do it only to see the number go up will end up never leaving the house and losing it all