I'm late to this thread but here's a further consideration.

I avoid connections because every (international) flight means another airport security checkpoint. I have a metal hip implant and set off the WTMD and get the deluxe groping. I know I have to do it at departure; avoiding having to do it all again at a connecting airport is worth a lot to me.

You must be the first person I've heard say this. Connecting in the US when you fly TO the US means going collecting your bags and re-checking them. Also, there is usually another security check involved, with naked scanners et all. Yuck!

I prefer European airports. The lounges are much better and the airports are usually more pleasant.

I love connecting flights especially the non stop. This is a great time saving to myself. I can easily do my other important works of the day in time. It's give me a lot of benefits.

?

I live in the NYC area, and the closest decent J lounge I've visited is at IST.

But, I would prefer connecting in European airports because many of them have supermarkets en situ.

I particularly avoid connecting flights on holiday/vacation.

I just can't be doing with the hassle of twice security, twice hiking to/from gates, twice hanging around and so on. Things that I would put up with on a business flight but seriously detract from a leisure flight. I do enough of that stuff for work. I really don't want it on holiday.

Two hours added to a four-hour trip is not insignificant. It's 50% more - earlier departure and/or later arrival - and for what?

I only take connecting flights if no other options are available or if the direct flight is way too expensive. Living in NYC, some airline is flying direct to basically every location globally. It's just quicker to get to.

That said, I've learned my lesson about taking direct NYC flights to certain small markets. For example, I fly to Charleston from NYC occasionally. Delta flies direct from NYC to Charleston, but those flights are vulnerable to being canceled. Much better to fly through Atlanta (where you will be on an Airbus/Boing then on an E-Bird) as Delta doesn't cancel as many ATL flights.

Perhaps your friend prefers unknown airlines if they offer non-stop
over a more known airline.

My preference in that situation would be for a more known airline
unless there are other circumstances involved.

Personally, I will not fly with the cheapo or the unknown airlines.
And at this point I still prefer non-stop over connections.

While I enjoy flying my focus is on getting to the destination
unless there happens to be a location along the way I want to see.

I thought I am the only one. Unfortunately for me, my home airport do not get any flights from the States so I am always stuck connecting. It is something about all the waiting and the whole process after the long flight - I can do 2 flights, 6-10 hours each with no issues but the 1-2 hours ones after the long flight (or series of flights) are killing me for some reason.