Why is my actual ride payoff sometimes lower than the estimated fare?

This is just because the ride fare you see in the Skeddy app at the time the ride is assigned to you is just an estimated fare but not a guaranteed payoff amount.

We receive these estimates from Lyft, as follows:

To save space, we calculate an average between the two edge values and show it to you in the app, as follows:

The actual ride payoff is always close to the estimate:

The above amount is always used to calculate the credits deduction for the ride.