Eating potatoes in moderation while trying to lose weight can be good for weight loss.
But if you eat too many potatoes then you could actually add on the weight since you'd be eating too many calories and saturated fat.
Also if you're eating potatoes for weight loss avoid eating anything such as butter or anything else high in fat or cholesterol along with the potatoes.
If you do eat some butter with the potatoes avoid putting too much butter on the potatoes.
Also you need to exercise in order to lose weight and burn off the calories you intake.
Weight loss requires you to burn off more calories than you intake so get plenty of exercise while eating a healthy diet if you want to lose weight fast.