I agree that delays are unavoidable. There will always be an obstacle in the way whether being a product problem. But if there is a scheduled plan on how to go about the project then the risk of delays will reduce. The plan shall consist team mates schedules, test plan, fabrication schedule, and other like buying materials. There should also be constant communication so there would not be any misunderstanding, everyone should be on the same page in order to follow the schedule plan. Group members should also put in the effort in the project because everyone has a task and if one is having trouble, it is always best to help. The leader should choose the right members if they have a choose if not they must be on the members back in order to assist.