Final answer:
To underestimate someone means to undervalue or misjudge their abilities, leading to incorrect assumptions about their potential.
Step-by-step explanation:
When you "underestimate" someone, you are likely to undervalue or misjudge their abilities. To underestimate someone is to make a judgment that is too low about their capabilities, performance, or potential. This often leads to unexpected outcomes where the underestimated individual may perform better than anticipated, proving that the assumptions made about them were incorrect.