The number of units on a lot is influenced by more than how many a manufacturer has put together: dealer inventory is limited to what their finance floorplan can support, which fluctuates based on their use or abuse, bank changes based on their cost of money and changes to exposure. Dealers have been operating 'out of trust' for years. Some get caught, some don't. It's not a big deal for most, but has the same effect as you getting caught flirting with your girlfriend's best friend....

There's a recovery period.
Inventory levels can be radically impacted by 'favored nation' contracts....these are guarantee delivery contracts that step in front of dealers who haven't negotiated such agreements with manufacturers.
Manufacturers distribute to dealers based on A,B,C status...just like the grocery business. Small operations, are less impactful and have 'empty shelves". And then there's the crystal ball used in purchasing....which operates more like a magic 8 ball for some.
The moral, keep looking.