In the economy of user effort, be a bargain, not a scam 

A model with surprising predictive power is to treat user effort as a currency that users are spending to buy solutions to their problems. Nobody likes paying it; in an ideal world software would read our mind and execute perfectly with zero user effort. Since we don’t live in such a world, users are typically willing to pay more in effort when they feel their use case warrants it.

Just like regular pricing, actual user experience often depends more on the relationship between cost and expectation (budget) than on the absolute cost itself. If you pay more than you expected, you feel ripped off. You may still pay it because you need the product in the moment, but you’ll be looking for a better deal in the future. And if you pay less than you expected, you feel like you got a bargain, with all the delight and loyalty that entails.

Source: In the economy of user effort, be a bargain, not a scam • Lea Verou