OK may sound wierd but it’s happened to me enough where I need to mention it. Because over packing is so prevalent I swear that some customs / immigration offlcers view a single traveller like me with only carry on as some red flag… Ask questions like “you don’t have any checked baggage?”, “this is all you have?”… I’ve been selected for random searches like that enough times to think it’s not a coincidence. “you are travelling for 3 weeks and only have carryon?” answer “I use laundry service on the trip” reply “step this way”, and they proceed to pull everything out of my bag and check every crevice lol. Just a heads up 🤷 EDIT :my travel is international to the carribean and south America so the red flagging would be more likely… Domestic US or CA flights would probably be less likely to experience this
it often depends on how ticket was booked. Roundtrip with one airline is less suspicious. Booking one way with limited packed bags gets a frown. I have travelled for work and the odd things were some security guy was concerned I travelled with two lap tops, and I got hand swabbed. And had additional security screening at each change over. But I also have had the opposite a few times: 1) push this randomizer, red you go through security protocol, green you get a pass all the way through the easy route. it lit up green and the person was legit surprised and confused that it showed green. 2) there was a military funeral years ago, i happened to be in the airport most people flew out from. i am not military. But had a buzz cut and good posture. The passport screener waved me through to the nexus line. I get to there and they are like where is your nexus pass. i explained I didn’t have nexus and that person sent me here. They just took my word for it and I zoomed through. so security can be a joke