You need to charge your customers in ways that they want to pay.
How Big Is Your Market?
Market Size = ARPU x Total Customers In Market x % You Think You Can Capture
Additional Reading
The Model Market Fit Threshold & What it Means for Your Growth Strategy - Brian Balfour
Model Market Fit is the concept that your market (and # of customers within your market) influence your model. The first time I heard about the underlying concept of Model Market Fit was from Christoph Janz @ Point Nine Capital.
www.brianbalfour.com
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