In the meantime, that deal qualifies as a nudge that violates all three of my guiding principles: The offer was misleading, not transparent; opting out was cumbersome; and the entire package did not seem to be in the best interest of a potential subscriber, as opposed to the publisher.

I ran into another type of bad nudging when I tried to book a ticket on United Airlines to travel from Chicago to New York. Before the airline would allow me to buy online, it required that I indicate whether I wanted trip insurance. This sort of required choice is justifiable when there is a genuine concern that the consumer might make a big blunder. I would endorse posing such a question to anyone opting out of all of an employer’s sponsored health insurance options, for example. We wouldn’t want someone to go without health insurance just because of a careless oversight.

United went a step further, though. It asked me to select “yes” or “no” before buying a ticket and highlighted the “yes” option as “recommended.” Required choice plus a recommendation qualifies as a strong nudge. But is it a nudge for good?

Consider the details: The trip insurance would cost $20.13 for a flight that itself would cost only $300. Keep in mind that the insurance covers just the nonrefundable portion of the ticket. (Normally the charge for changing a flight on United is $200, and the insurance would cover this.) I also learned, deep in the fine-print weeds, that to collect on the policy, unless the flight were canceled or delayed, I would need a doctor’s note saying that I was too sick to fly safely, and would have to file such documentation within 72 hours of canceling the trip.

If my flight connected up with a cruise, the insurance might make sense, because with the insurance I could receive compensation when a delayed or canceled flight made me miss my rendezvous with a cruise ship. But I wasn’t going on a cruise.

As an alternative, I examined a fully refundable ticket, which would cost $856. United still recommended trip insurance and charged more for it ($49.23) even though this ticket was refundable. Rahsaan Johnson, a United spokesman, said the company recommended “insurance to protect against unintended expenses that may result from circumstances beyond the travelers’ and the airline’s control,” but said the pricing is set by Allianz, which provides the insurance. Daniel Durazo, an Allianz spokesman, said it priced the insurance as a percentage of the ticket cost, but would not say whether that formula made sense.

On the positive side, opting out of these offers was easy, but the nudges flunked my other tests: They were neither transparent nor in the best interest of most customers.