LOL
Happens to me all the time. Not only prep items but others too.
I work in my home-workshop time to time and almost every time I miss something. Tools are there but maybe hiding in this kit or that kit, or in the other desk dedicated for computer repair ( I have a desk in a corner for minor jobs, and a room for bigger jobs)
Lately, I canceled the minor repair desk thing and shifted all the contents ( tools, supplies) to that workshop. Now it is properly equipped without buying anything extra.
Too many kits result in you having NO tools when you need them, especially when kits become too holy to be opened and used. In my case it has become ridiculous as I have a tool kit in the garden (with general items plus garden specific stuff), another for the ground floor(general/electrical) , another for the attic(general/mechanical), another for when I go to Mom's house ... etc. It was logical and understandable when I made them but after some time it has become apparent that multiple kits is not always a good idea.