TL;DR
When bots pick the last item from your inventory that you are using to build and you have the configuration "pick ghost item if there is no item available", the item in your hand should be turned into ghost.What ?
One of the most annoying things in the game when you are starting to have some bots, is that you are either crafting and building or expanding your base while you have a set of items in your inventory, end it will eventually run out as normal.A very simple example of it is placing belts, lets say you start with 100 belts in your inventory, then you start placing them and design your build.
But as you are placing and moving it around, at one point the bots will pick up the last belt from your inventory, and at that precise time if you were placing belts, it will just disappear from your hand instead of turning into ghost.
It become even more evident if you are hand assembling the items while the bots keep taking it away, as it became impossible to shift drag for ghost.
As you have like 1 or 2 items on your inventory while more is being crafted, so you start to shift drag but the bots take the 2 you have and the item vanish from your hand.
Why ?
It is just way to annoying having the item vanishing from your hand when you already have an option to use ghost available in the game.Ideally one should be able to place the belts/ghosts with one continue motion instead of those constant stops in between. At least when you are forcing ghosts with SHIFT + Drag.
I'll try to add a gif showing it