I think it is a combination of carrots and sticks.
Carrier says state "incentives" were an "important consideration," along with Trump's commitment to creating a more pro-business climate in the country. Those would be the carrots. Then there are potential sticks, which may have been far more critical than tax incentives or other potential subsidies.
Carrier's parent company, United Technologies, is a large federal government contractor and perhaps views the potential costs of keeping those factory jobs — a small fraction of the company's 200,000 employee workforce — in America as the price of doing business with Trump's "America First" administration. Indeed, one Indiana official, Politico reports, thinks the deal was driven by concerns United Technologies "could lose a portion of its roughly $6.7 billion in federal contracts."
Not sure if this is good economics at all.... is Trump going to continue doing this for every single big company that is thinking of moving operations abroad?