According to Samir Tandon, an expert watch collector, the purchase of a high-value item like luxury watch should be based on evaluation of several factors, such as brand, design, safety features, strap, movement & mechanism, and availability of service centres. It is very important to have accessible service centers of the brands you own. Tandon feels a mature collector looks for old brands that have endured the test of time and prefers watches to have a simple design with the basics of time, date and day. The edges of the strap need to be smooth and the weight of the watch must be equally distributed across the band on the wrist. Safety and protection are important — the watch should have sapphire crystal, as a minimum protection of the view area (front and rear for automatic watches), the bezel should be raised above the front glass and the watch should have at least 1ATM water resistance.