Depending on how much my starting bankroll is, if I started with no more than $50 then I will be happy enough to take $50 profit. But if I started like with few hundreds dollar, I cant be really happy to win $50. Although in fact $50 is something that can be considered as a good amount in my country but gamblers usually use their starting bankroll/deposit as the main reference to set a target on how much they want to gain with their deposit, not based on how much is the value of the winning in their country.
I think that OP is talking not about how much percent of deposit you win but about the cost of money. We can`t understand emotions of the authors here, when they call the sum they win. But if authors will write something like "i won my monthly salary" or will add something like "$100 is medium salary in my country" it would be easy to understand how big profit for them.
I guess you misunderstood what "Bitinity" meant when he said
"If I started like with few hundreds dollar, I cant be really happy to win $50", because literally, the O.P just asked a basic simple question, which was "Can winning $50 make you incredibly happy?". Of which before any answer to this question must be made, then the amount that was deposited into the casino also need to be put into consideration. Because you literally don't expect someone who deposited $200 for gambling, and ended up winning just only $50 to be very excited, Unlike a user who might have deposited just only $10 and ended up winning $50. Because though $50 is quite a reasonable sum of money in my country, of which an average gambler will be happy to have won it.