In a heated confrontation, many things can go wrong. A strike you do not see is the one that hurts the most. Perhaps the worst you can do is getting within striking range of the other person. Pride, and cockiness often results in you underestimating the person and “begging” them to throw the first strike.
In cases like these, it is obvious that when a person does this, they do not really want a full blown match like they suggest. It is the case of all bark and no bite. When the other person throws a strike at such a close range, even with bad technique (as it is with every untrained person), it can still rock the person.