But what caught me by surprise was just how much I wanted to hold onto that 5.0 rating. If I have a babysitter who watches my toddler in the evening, I’ll often call her an Uber home. But all of a sudden, I worried: Babysitter A can be a bit surly to strangers — would her attitude on the eight-minute ride home to her house cause my own rating to sink? I began giving my babysitters $5 extra on their way out, imploring them to add that as a tip at the end of their ride.

So, anyway, that’s my system: Ride on other people’s accounts whenever possible, be as chirpy and friendly as if I’d had three cappuccinos, and make sure to throw a few dollars in for a tip at the end of the ride.

I know that’s insane.

But I’m not alone. My friend Sam still holds a grudge from the time he sprang for an Uber after a wedding and one of his friends threw up, dinging his rating and causing him to have to pay a $150 cleaning fee. His friend offered to reimburse him, but for Sam, what really stung was his new 4.4 rating.

“Look, I appreciated that my buddy reimbursed me, but I use Uber all the time. So it’s like…when I’m stuck in the pouring rain trying to get home and I can’t get an Uber, I am not happy.”

Another friend, Jenna, has a similar story. She recently went on a third date and was appalled at the way her date treated the Uber driver (which she had booked through her app). “He was giving directions, but not in a Hey, this works best way — in a really know-it-all way. And we were going to my neighborhood, which he clearly didn’t really know. He was just doing what his own personal GPS was telling him.”

Sure enough, when Jenna checked her Uber rating a few days later, she’d tumbled to a 4.8. “I blame him. And I guess I would have felt the same sense of outrage if we had been in a cab, but I think the rating has this long-term repercussion: It shows your behavior matters.”

It does matter — but, as I also recently learned, it’s totally random, an algorithmic equation that has nothing to do with who we are as people.

After I had my girls' night out with my friends, we rode home, still on Jen’s account. When our friend Stacy hopped out at a light close to her apartment, I slammed the door behind her.