I have always set goals and when I lived in the USA I had the goal of flying in and out of the Top 100 US airports by passenger numbers. I appreciate it changes slightly each year but I kept up with those changes. I also had the goal of flying in and out of all 50 states which I also achieved. I am now living back in the UK so I have set the goal of flying in and out of the top 20 UK airports and also all 6 main London Airports LHR, LGW, STN, LTN, LCY and Southend.
I am interested in what flying goals if any, others have set.
Interesting question.
Not in the same way as railways with track scratching, but some vague ambitions.
I was trying loosely to scratch all commercial airports in countries I travel to regularly but that's a mad idea in many countries.
In the Netherlands I'm only missing Groningen, which is pretty sparsely served.
In Afghanistan I'm missing Mazar and Kandahar (Mazar likely scratched in September).
Belgium has a surprising number, with most summer seasonal. I'm missing Antwerp, Oostende and Liege.
I have however cleared Luxembourg and Moldova which is admittedly a bit of a fudge (there's only one).
Where feasible I like to scratch all airports in a city where there are multiples: I've scratched all London airports, the three Milan airports, 2 Rome, 2 Nairobi, 2 Brussels, 3 Istanbul.