Item go missing in security check

[RevMan2]

I can't stop them stealing from my checked luggage (Opinel knife from the side pocket LAXFRA. Again...) but you can de-risk carry-on theft as follows:

Before you get anywhere near security, put EVERYTHING from your pockets in your carry-on.
If you're selected for secondary inspection (I invariably am - various metal implants..) say in a VERY LOUD voice "I want to have clear visibility of all my carry-on items while you're carrying out this inspection"
If they get stroppy, say "You are NOT performing this inspection until you have retrieved my carry-on items"
Further intransigence: "Get your manager"

Never fails.