Is it random which items are lost upon mission failure?

I'd have assumed that items getting destroyed during mission definitely gets rid of them so this isn't about that...

I've noticed that sometimes when mission fails I lose majority of armor and equipment soldiers had instead of everything and sometimes they don't seem to lose much at all. Is there some kind of mechanic where like 1/3(or none) of equipment is recovered after mission failure? I'd have first assumed that this would be like first xcom where you lose everything if you fail, but it seems I don't lose everything always?

I never actually noticed that I lost anything. But I haven't tested it all that well yet.

I think if you loose soldiers during a battle, you can still retrieve the equipment of them when successfully completing a mission. But upon completely failing a mission, I believe that all the equipment will be lost.

if explosives are used to kill a troop or an explosive goes off where the dead troop is, you'll lose all their equipment. i have also noticed armour can be destroyed, and I've had various weapons destroyed right away. as they are not even recoverable during the mission.

Actually it depends on how your soldier was killed. If your soldier gets an overkill (like when you see aliens being completly blown by a grenade) you will loose all of his equipment. If they are killed ''only'' by a bullet and you still see their copse you will get the stuff back.

ps: by the way when you overkill an alien you wont get his stuff either. Meaning you will get less money at the end of the mission.