My wife and I were walking back from dinner in Lisbon when we heard an alarm.
We weren't alone. People were leaning out of their windows, wishing the noise would stop.
It wasn't coming from a car. It was an electric scooter, presumably out of juice, that had been strewn onto the sidewalk like a toy that had had its day.
Who knows when it was retrieved? Who knows who had been riding it and the three other scooters dumped alongside it, blocking the sidewalk?
The question is whether anyone cares.
The scooter plague has now infected so many cities.
At SXSW in Austin earlier this year, people merrily rode their scooters helmet-less down the middle of the road. Because it's just so cool. Most didn't care about traffic signals, pedestrians or any cars they might be blocking.
They were like a bunch of Leonardo DiCaprio's at the front of the Titanic, believing they're the kings and queens of the world.
I confess to laughing when one scooter rider stormed down a sidewalk, dodged past several pedestrians, tried to brake and toppled over.
A restaurant server told me her favorite moment was when scooter riders don't brake at sidewalk intersections and T-bone other scooter riders who have stopped on the other side and are waiting to cross.
Often, these scooters arrive without city permits.
In Lisbon, they're everywhere. Riders are completely indiscriminate about where they ride and where they dump. It's as if the whole city is their little playroom and mommy and daddy can pick up after them.
Meanwhile, everyone else has to step over and around them.
I tried to accept this as the way of the new world. Until, that is, we were walking past an arrangement of two bronze statues, created by Sérgio Stichini. The sculptures honored those who had paved the city.
Yet a customer of Flash electric scooters decided to dishonor the whole thing by parking their scooter right in the middle of the sculptures. (The evidence is below.)
Naturally, I contacted Flash and Lime -- two of the companies whose scooters I've seen most often dumped around the city.
Lime didn't immediately respond. Flash, however, insisted this was all the fault of soccer fans. One of the two local teams, Benfica, had just won the Portuguese League for the 37th time.
So, the Flash spokesman explained: "It was an exceptional period, with many people celebrating and not always thinking about where to leave our vehicles responsibly. It is not reflective of the city normally."
Well, this is our third week here and it's entirely reflective of the city we've normally found and know well.
Every day and night we've seen scooters abandoned in random spots. On a Saturday night two weeks ago, for example, we watched an elderly lady carrying her shopping and clambering over a prostrate machine on the sidewalk.
Perhaps this had been left by a disgruntled Sporting Lisbon fan after his team's abject draw against lowly Tondela.
The Flash spokesman, though, insisted this simply isn't a problem for his company: "We promote specific parking areas, something that's praised by the city officials, who are contemplating asking others to do the same. Most of our riders use these areas and we offer a small discount for responsible parking. It's working so well that we are the only company authorized to work in as many as seven Portuguese cities."
I fear, though, that many of these scooter companies might offer the same excuses as so many other tech companies.
Well, we created something that we believe helps make the world a better place. We could never have anticipated that some people -- a tiny minority, of course -- could be so disrespectful.
Why, at a meeting in Oakland, Calif., a Bird executive dared to put some blame on parents for letting their kids ride the scooters.
Yet in every city I've seen these Segways For The Demented, the situation seems the same. A new form of recklessness that defies good sense and a new form of litter that's a blight on the landscape.
It's not surprising, then, that the Centers for Disease Control and Prevention are running a study of scooter-related accidents.
If it's not possible to identify the miscreants who dumped the scooters in this way, should the companies be fined for every instance? Yet there seem to be so many instances that reporting the majority would be impossible.
Proponents of these scooters claim this so-called micromobility revolution offers a cleaner future. A sustainable one, too. Well, that's if the piles and piles of obsolete scooters don't create their own environmental issues.
Then again, don't they discourage actual exercise? Why, after I'd stared at the desecration of the paving laborers sculpture, we walked a few paces away.
In the square opposite was a group of stationary exercise bikes displayed as part of a "Portugal Activo" presentation.
No one was on them.