Hi,

The state of a picking depends primarily on its moves, it is a funcion field:

* If any move is draft, the picking is draft
* If all moves are done/cancel, the picking is done/cancel

The other states depend however also on the move type. The move type determines whether the customer expects to get all products of a picking at once (=all at once) or he wants it delivered to him as fast as possible. (=partial)  This move type can be determined manually, or can e.g. come from a sale order where it will be passed through the procurement group. 

In case of partial, a special state exists: partial availability.  It is possible that a move is in the confirmed / waiting state, but has partially some stock reserved.  This move will still be in the waiting/confirmed state, but have a flag partially available.  In that case, the picking will not stay in the confirmed/waiting state but go to the partially available state, which makes it possible to deliver the goods partially.  A picking is also partially available when some moves are assigned and others have no stock at all reserved. 

Sometimes a move does not have a picking type.  This means it will not be assigned to a picking.  This is the case for inventory corrections and moves in and out of production.