There was one farmer, deceased now, who was notorious for his use of the clutch. He always bought his cars at the local garage, who, when he changed vehicle, would order a new clutch the day he took delivery and then another every time they replaced it. It was the complete clutch they used to replace, not just the clutch plate, 'cos other elements of the clutch mechanism would have been cooked as well.A manual might fail at 100,000 miles as well. I remember a time, not so long ago, when gearboxes generally needed an overhaul at 50,000 and cars were very unlikely to travel 100,000 before being scrapped. I also know a driver that is so rough with his gearbox that almost every car he drives has the gear-lever break off in his hand at some point and he can't understand why car manufacturers have not sorted gear lever and gearboxes out in this day and age.