Dr. Shu and Dr. Gneezy demonstrated another effect of this fallacy by giving people gift certificates good for movie tickets and French pastries. Some got certificates that expired within two to three weeks; others got certificates good for six to eight weeks.

The people who received the long-term certificates were more confident than the others that they would redeem the gifts  a logical enough assumption, given all the extra time they had. But they just kept putting it off, and ultimately they were more likely to let the gift go unredeemed than the people who had received the short-term certificates.

Once you start procrastinating pleasure, it can become a self-perpetuating process if you fixate on some imagined nirvana. The longer you wait to open that prize bottle of wine, the more special the occasion has to be.

If you’re determined to get the absolute maximum out of those frequent flier miles, you can end up wasting them, as Dr. Shu found in an experiment offering people a chance to use discount coupons in the course of buying a series of plane tickets. Once the subjects were told that they might have a chance at a free flight worth $1,000, they scorned lesser awards and hung on to their coupons so long that in the end they had to use them for much cheaper flights.

“People can become overly focused on an ideal,” Dr. Shu said. “Even if they know it’s unlikely, they get so focused on the perfect scenario that they block everything else. Or they anticipate that they’ll kick themselves later if they take second-best option and then see the best one is still available. But they don’t realize that regret can go the other way. They’ll end up with something worse and regret not taking the second-best one.”

But even if you know about all this research, how can you apply these lessons? How can you avoid the temptation to postpone pleasure? (You can offer suggestions at nytimes.com/tierneylab.) One immediate strategy, Dr. Shu said, is to cash in quickly any gift certificate you received this holiday season. “The biggest danger is that it will be forgotten and expire,” she said. “One of the best presents you can give back to the giver is to use it quickly and then tell them how much you enjoyed it. The regret from not using it will be bigger than the regret from using it on a nonperfect occasion, for you and especially for the person who gave it.”

Another tactic is to give yourself deadlines. Cash in the miles by summer, even if you can’t get a round-the-world trip out of them. Instead of waiting for a special occasion to indulge yourself, create one. Dr. Shu approvingly cites the pioneering therapeutic work of Dorothy J. Gaiter and John Brecher, who for the past decade used their Wall Street Journal column on wine to proclaim the last Saturday of February to be “Open That Bottle Night.”

But you don’t even have to wait until Feb. 27. Remember the advice offered in the movie “Sideways” to Miles, who has been holding on to a ’61 Cheval Blanc so long that it is in danger of going bad. When Miles says he is waiting for a special occasion, his friend Maya puts matters in perspective:

“The day you open a ’61 Cheval Blanc, that’s the special occasion.”