Correct, you can always save indefinitely to get the required amount of money and pay for whatever all at once. The problem is that the above is assuming that

Correct, you can always save indefinitely to get the required amount of money and pay for whatever all at once. The problem is that the above is assuming that there is no value to having the thing you want to buy. For example: a person might be able to save for 12 months to buy a new camera, but that's now 12 months they don't have that camera. Presumably you had reasons for wanting that camera. While there are a bunch of things I don't think it's ever good to go into debt for, your claim that there's no justification other than "I deserve to treat myself like a king" is BS. As per usual for articles like this they pose this in context of the extremes "sandwich in payments", which I suspect if people have done that it is accidental and/or "huh? what is this like".