What’s the matter with Bill de Blasio? The mayor of Gotham announced he is running for president on Thursday morning, but no one seems excited—not the voters in national polls, not the chattering classes, not the diner denizens of Iowa and New Hampshire, and not even his home city. In an April poll, three out of four New Yorkers said the mayor should not run.

There’s nothing wrong with the idea on paper: De Blasio is fairly popular, with 17-point favorable ratings among New York City Democrats. He has especially good numbers with black voters—a characteristic he shares with current Democratic presidential front-runner Joe Biden.

De Blasio has about as many constituents, as a mayor, as presidential candidates like New Jersey Sen. Cory Booker and Washington Gov. Jay Inslee. He’s got a few marquee achievements to his name, including police reform, free legal representation in housing court, and a blue wave in state politics, for which he deserves some credit. As his supporters sometimes point out, there are almost as many children each year in de Blasio’s signature pre-K program as people who live in South Bend, Indiana.

So why don’t New Yorkers want him to run? The simple answer might be: We’re offended that he doesn’t consider this a full-time job. To watch de Blasio prepping his campaign in Iowa and New Hampshire over these past few months has felt like a slight. It’s also the culmination of a long-term drift in the mayor’s attention. In his first year, Hizzoner spent an average of 19 days a month in City Hall. By 2017 and 2018, that had dropped in half. He treats riding the subway as a chore and doesn’t care for the local sports teams. He genuinely seems more interested in national issues than local ones.

Which might be fine, if it didn’t so neatly reveal de Blasio’s central fault as mayor—one that would trail him, and hamper him, as a left-wing president: He doesn’t sweat the details.

De Blasio’s is a hunch-based politics, one where instinct comes before evidence and management is an afterthought. In some ways, that instinctual tendency has been a welcome relief from the technocratic style of his predecessor, Michael Bloomberg. It certainly makes him a better politician. De Blasio’s decision to end the New York Police Department’s stop-and-frisk policy, for example, was courageous—and his gambit was vindicated by crime rates that haven’t stopped falling.

Yet on other fronts, the mayor’s aversion to the messy businesses of data and management has not served him well. That might be an acceptable weakness in a Republican candidate—the president shouldn’t be a micromanager—but it’s a clear problem in a politician making a pitch for bigger, better government. For Democratic voters who expect sweeping federal initiatives like a Green New Deal or “Medicare for All,” big ideas will only be as good as their implementation.

In New York, the mayor has let his habits guide him to some strange places. Look, for example, at his signature transportation projects. De Blasio has put hundreds of millions into a ferry system that offers heavily subsidized rides to a small number of wealthy waterfront residents and tourists, then declared the boats “a new form of mass transit” that could help alleviate crowds on the city’s subways. (They couldn’t.) His other flagship project is a mixed-traffic streetcar, projected to be of little use, connecting those same neighborhoods. These are underwhelming, wasteful projects that barely address the city’s gaps in mass transit. As for the city’s actual transit ridership? It’s all on buses—which have deteriorated rapidly under the mayor’s watch—and subways, the responsibility for which de Blasio has been very, very happy to cede to the governor as the system has tumbled into crisis.

It seems like inside baseball, but it’s part of a trend: De Blasio seems to have trouble letting evidence override his preconceptions, and is reluctant to get his hands dirty when problems arise (see: the New York City Housing Authority). Perhaps the most obvious example of this reflexive governance was the mayor’s long-standing opposition to the idea of congestion pricing, a toll on drivers entering Manhattan’s central business district. For years, de Blasio insisted that charging drivers to use the bridges (and transferring that money to the transit system) was a “regressive tax”—despite studies showing that just 4 percent of outer-borough workers commuted to work in Manhattan, and just 4 percent of those were poor. An executive who went first to the numbers would have come to a different conclusion.

Another case study in the mayor’s anecdote-driven policy agenda is his opposition to electric bicycles, which immigrant deliverymen use to take meals to, well, everyone else. Initiating a police crackdown on the drivers, de Blasio said the bikes were “just too dangerous.” Later, Streetsblog collected the data: E-bikes injured 32 people in 2018 out of 61,939 total collision injuries on city streets. Twenty-three of those injuries were to riders themselves.

This deference to what de Blasio already believes—a kind of intellectual stubbornness—is not limited to transportation. Last month, the mayor announced a crackdown on greenhouse gas emissions from skyscrapers, which would face steep fines if they failed to shrink their carbon footprint by 2030. He pointed to the glimmering new Hudson Yards development, derided as a playground for the rich, as an illustration of the policy’s class-war bona fides. On Wednesday, to further illustrate the point, he held an event at Trump Tower. That got him into a Twitter scuffle with Eric Trump (who is wrong on most of these counts, by the way), so, mission accomplished.

Spare me? First you have never created a job in your life. Second, our great city has gone to shit under your leadership. Crime is up, the men & women of the NYPD detest you, homelessness is rampant, our streets are dirty and people are leaving our city in record numbers. https://t.co/3Fn1glQJEa — Eric Trump (@EricTrump) May 14, 2019

But the logical gap in this plan quickly became apparent. It turns out that all the Trump Organization’s buildings put together would not accrue as many fines as the Bank of America building, which is one of the country’s “greenest” skyscrapers. It’s also one of the biggest. Indeed, according to the city, three of the five worst offenders of the policy are 55 Water Street, Google’s New York City HQ at 111 Eighth Avenue, and the MetLife Building—three of the city’s four biggest buildings by floor area. De Blasio was boasting of a tax to penalize the very thing that makes New York one of the most carbon-efficient places to live in the country: its density. He saw an attractive target in skyscrapers, not realizing that they are New York’s greatest green asset, because they permit everyone to live close together and not drive everywhere. The greenest thing New York could do would be to build more of them, so that more people could afford to move here from car-dependent cities and suburbs.

This is life in de Blasio’s New York, where the best-sounding policy always wins, and the most difficult issues often get overlooked. I could see the appeal after 12 years of Michael Bloomberg’s data-driven rule (“a culture of evidence,” the businessman-mayor boasted) which de Blasio criticized for exacerbating New York’s social divides. But data can work for the left too. For progressive government to thrive, it must.