예열플러그 대체 왜 부러질까?

Additional Explanation If you fix your own car, there's no need to discuss it with anyone. However, if the owner and the repairman are separate, it seems like they need to communicate and negotiate well. A stuck glow plug doesn't necessarily mean the glow plug body is less durable. If you approach it as if you were loosening a thin 10mm bolt, theoretically it won't break. However, it's possible that it could break if you force it, so it seems like it's a case of overzealousness. I mentioned that the stuck glow plug is the owner's fault, but I can't say for sure what causes it to stick. I wonder if it's just luck, but poor maintenance of consumables seems to increase the likelihood of it sticking. Driving as normally as possible, changing consumables regularly, keeping the oil tank as full as possible, and occasionally using fuel additives all contribute to a lower chance of it sticking. This is my personal opinion.