No doubling at all. Win or lose. That's what I do. I don't really mind just playing on the same amount at every roll or even in sports betting because I don't want to have that greedy habit that could also ruin me in the long run. I think I am satisfied adding some spice on the sports games by adding a bet on it.
Let's not waste too much money in gambling. If we win, let's withdraw and enjoy it. If we lose then stop for a moment and think about whether we should deposit more or we can take the day off and just call it a day.
That's actually what gamblers should do, but most people can't do it, some because they can't control their emotions once they lose, some because they want to have some fun when they win, so they go ahead and increase their bets. The ones who had lost do it to recover their losses, and the ones who won do it to experiment with the money they've already won, only to see if they can win more with it or not. However, as you said, it's carelessness, and one should be aware of the possible outcomes and then decide whether they want to do it or not.
Usually, those who do it for fun or experiment wouldn't be bothered much even if they lose, but the ones who double it because they've just lost the previous bet and want to recover their money, they will have a hard time letting it go and going back to their original betting amount because now they have lost more money and they want to recover that as well.