It depends on your funnel consistency. If you are selling a self service product with transparent pricing, fully realized ARPU can be a solid number. It will ch

It depends on your funnel consistency. If you are selling a self service product with transparent pricing, fully realized ARPU can be a solid number. It will change as your customer base changes, and there still could be outliers, but it's decent and easy to reason about (and project with). If, however, you are kind of self service, but do an Enterprise sales deal ... you have two funnels with two vastly different customer profiles. Not only is ARPU bad in this scenario, most numbers are. The trick is narrowing the scope of a given metric enough that you can use it to make good decisions, and but not so much that it ignores important parts of a business.