If you want to buy right watches, you should know how the watches work. The important part of watch is movement. In modern watch manufacturing there are two main types of movement, quartz movement and automatic movement.
Quartz watch keep time by a battery, the majority of wholeslae watches for kids use quartz movements as they're cheap to make and extremely accurate. However the automatic watch is one that rewinds the mainspring of a mechanical movement by the natural motions of the wearer's body. The real watch lovers prefer to collect automatic watches. The top brand watch company such as Rolex, Cartier, their classic watches are used in automatic movement.
Despite the quartz watches is cheaper than automatic watches, but it is always wear on wrist. And if an automatic watch broken or needs repair, you should have it repaired only by professional watchmakers, otherwise they often carry a larger damage. So you will waste too much many on the automatic watches. The quartz watches is more practical.