Market size is the easiest number in a growth plan to inflate. It is usually the total spend across a category, not the number of companies that could buy this product at this price.
Turn the market into a list
Ask for the count of companies that fit the product at the deal size the plan needs. If the plan needs large deals, the market is the number of firms that can write a large cheque, and that is a much shorter list.
How many companies can buy at the deal size the plan needs?
Then check it against the plan
- Divide the new revenue the plan needs by the average deal size.
- Compare the number of deals that implies with the number of buyers on the list.
- Ask how many of those buyers the sales team has already spoken to.
If the plan needs a large share of a short list, the market is not big enough, whatever the headline number says.