Why did Piero lose interest at the last minute?

Normally, I wouldn't ponder such small plot details in a film that is not trying to tell a story with a conventional narrative structure. I think it would be easier to dismiss Piero as someone so shallow and out of touch with his emotions, that he would act more on whim and impulse, but knowing that each scene is carefully crafted with meaning, I can't help but feel like there was more going on in his head in the scenes where he walks Vittoria to the door and then returns to his desk. And if so, whatever his motivations were in that moment, it must have went over my head.

If Piero was just your typical player that uses and then dumps women, then why did he feign interest until the very end? It seems to be more his nature to be brazenly upfront and dismissive of people once he no longer has any use for them, e.g. the woman on the street and the people in his office. This leads me to believe that he genuinely was smitten with Vittoria, but for whatever reason, changed his mind and decided not to show up at the meeting spot, or to continue pursuing her. Or is the point of the film to say that our modern-day approach to love and relationships is so fickle and superficial, that we don't need a reason, and it just boils down to "he's just not that into you" or "out of sight, out of mind"?