We have to consider it from three different situations:

1)If the variable resistor is only connected the first(Left) and the third (Right)terminal, it won’t change resistance at all. Thus, it’s only like a fixed resistor.

2)If the first terminal (left) and the sliding end are connected at the same time, with the slider slips to the right, the access resistance will increase but the current in the circuit will decrease instead.

3)If the third terminal (right) and the sliding end are connected at the same time, with the slider slips to the right, the access resistance will decrease but the current in the circuit will increase instead.