Re: It's not "why", it's "how"
"How many US citizens (let alone people in the world) actually understand this process?"
Probably not many :-)
I was interested to see from the count stats that it appears Trumps party merely retained their share of the vote, Clintons party lost some of their share and the overall turnout, despite the press reports of "mass turnouts" amongst certain racial groupings, remained more or less the same. As an outsider, it seems to me that Trump "won" based on either Clintons supporters not turning out or voting for one of the other candidates in protest. In other words, Trump didn't "beat" Clinton, Clinton lost her own supporters to "don't like our own candidate, vote for anyone other than Trump or Clinton"