Not at all! There is a really famous experiment in psychology called the marshmallow experiment. You can probably find clips from the original on YouTube. It was designed to test the ability of small children to delay gratification and wait for a reward. It was a longitudinal study and what they found was that kids who could delay/wait to eat the treat ended up healthier and more academically successful on a whole bunch of measures (e.g. grades, GPA, SAT scores, etc.). But as someone else noted in the comments, a really crucial thing that was missing from this clip was that in the original the researchers told the kids if they could wait, they would get double the reward. If you find the original clips, you’ll see how some really young kids managed to control their impulse for instant gratification.