When selecting an ODM (Original Design Manufacturer) watch, you must prioritize the movement type, as it dictates the watch's reliability and price point. Common choices include Japanese movements (e.g., Seiko, Miyota) for a balance of cost and quality, or Swiss movements (e.g., ETA, Ronda) for luxury positioning. Additionally, verify the water resistance rating (ATM); for daily wear, 3ATM is standard, but 5ATM or 10ATM is required for sports or diving watches. Material selection is also critical—316L Stainless Steel is the industry standard for high-quality cases due to its corrosion resistance, while Sapphire Crystal is preferred over mineral glass for superior scratch resistance.