The agents filed somewhere cheaper.
You put a fee on every return an agent files through you. Agents see that fee on every single filing.
The fee: $1.99 an e-file, every agent, every return.
The CFO: Filing revenue tripled in one season! The agents can't stop filing!
OMNI: NOT SO FAST! $1.99 a return? There are other e-file providers. I tried every one before lunch.
By the next April, agents file elsewhere. A Thoma Bravo consortium takes Intuit private at 2x revenue.
The Buyer: 2x revenue, among friends. We'll keep TurboTax running. Someone has to file our returns.
Outcome: Lost as a feature
You charged agents for a filing they could send anywhere. They sent it somewhere cheaper, and Thoma Bravo took what was left.