My best guest, and this is pure speculation, is that skipping a meal makes people believe that they can eat whatever they want for the other meal(s) of the day.

My best guest, and this is pure speculation, is that skipping a meal makes people believe that they can eat whatever they want for the other meal(s) of the day. As such, they eat awful food and never develop good eating habits. I did OMAD (one meal a day) for a while and when I was researching it, many places encouraged this behavior. The idea being that if you skip 2 meals, even if you eat like garbage for your one meal, you won't be able to eat as many calories. This worked for me, I ate whatever I wanted for dinner and I lost ~20lbs in a month, but my cholesterol levels increased so I put a stop to it. Then, I put the weight right back on because, well, I never actually changed my eating habits -- only the frequency.