Is the ablution considered incomplete if the feet are washed more than three times, for fear that the water may not cover them adequately with only three washes?

A wash for a limb is not counted until it has been completely covered with water, even if it takes more than one scoop. If complete coverage of the feet with water is not achieved with three scoops, then it is obligatory to add whatever is necessary to achieve thorough washing, even if it is more than three. When a limb is completely covered with water, that counts as the first wash. If additional water is used after a limb has been completely covered with water three times, it is disliked but the ablution remains valid.