(CNN) Mark Cuban is, like Donald Trump, a flashy and controversial billionaire. He's also, to my mind, one of the most savvy analysts of Trump and the president's appeal out there.

In other words: When the Dallas Mavericks owner talks about Trump, I listen . Which brings me to Cuban's appearance on CNN's "New Day" Friday morning and his assessment of why Trump won. Here's the key piece:

"I call it political chemotherapy. One of my friends who I always thought was very smart said, Mark, I voted for politicians my entire life. He's in his 50s. Do you know what the definition of insanity is? Doing the same thing over and over expecting (sic) the same results. So I voted for Donald Trump. Is he poisonous in a lot of respects? Yeah. He's our chemotherapy. We hope he's going to change the political system."

"Political chemotherapy." That is a brilliant way to think about Trump.

Here's why: It was clear that even as Donald Trump swept to an electoral college victory on November 8, there were lots and lots of doubts about him even among those who voted for him.

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