Trump has always been hell bent on publicly proclaiming himself a winner. And for him, being a winner means not just being successful, but being the best. Better than anyone and everything at whatever he does.
It’s not enough to be rich; he has to claim he has more money than he actually does (I’ve actually heard first hand stories about this from a former Forbes journalist). It’s not enough to screw starlets and gold diggers; he has to “anonymously” phone the press so that everyone can know about it. It’s not enough to host a long running, highly rated tv show; he has to claim its failure to win an emmy damaged the emmys’ credibility. It’s not enough to win the presidency; he has to claim he won the popular vote because millions of people supposedly voted illegally, even though they didn’t. It’s not enough to take the oath of office in front of the entire world; he has to claim more supporters showed up at his inauguration than for any other president, despite the all the aerial photographs revealing him to be a infantile liar.
He can’t help himself. He must lie and lie and lie, exaggerating every legitimate success and adamantly denying anything remotely smelling of failure.
No wonder then that of all the many insults that Trump lobs like handfuls rice at a wedding, in his mind the biggest, baddest epithet he can hurl at someone is “Loser!” Because losing is sad.