Indeed, if there's no balance since you manage to control it then there's no way that you'll lose more than your allocated budget, it's wise to set it up before gaming, as lust inside you will push you to keep playing and that chance of adding more money can be done, unlike if you set everything before you begin, there's no way that you can top up if there's no available balance to add up.
Yes, you have to do it without a doubt, it is the healthiest thing to do and you can do it before playing or going to a casino, you have to say, I am going to spend 40usd (let's say) but those 40usd are not going to affect our daily life, so in this aspect that is what we can spend per gaming session, so with that premise there is nothing else to decide, if the person loses then they have no choice but to accept it, by losing what you are willing to lose I think that nothing is Softened in our life.