You can fly from A to B to C without landing at A or B...
Most of us only log airports we land at, but there is no requirement there outside the context of requirements for a certificate. But for some certificates you really do have to log landings, and to prove currency, you need landings (and takeoffs!) logged, including whether they are day/night or full stop. One a lot of people miss is that for night currency, you need three night takeoffs in the last 90 days. It doesn't count if you take off 30 minutes after sunset and land 65 minutes after.
An instrument cross country is an example where there will be multiple airports (and at least three approaches) logged, but perhaps only one landing.