How do I pick a winning product to sell on Amazon?

Always look for minimal competition, high (or moderate) demand products when starting a private label on Amazon. There are other factors as well for good product to sell on Amazon like
Search volume
Sales Velocity ( min 200- 300 units sell in a month)
Price range ( More $25 )
Profit ( should be 25%- 30% margin of profit
Less Reviews
Should not be seasonal product
Easy sourcing and shipping ( mean not to be damageable while shipping)

Check the search volume on the main keyword of the product and if it is good and has good search history and remains constant throughout the year and the product is not competitive in the market then it is a winning product.

You have to pick a product that has high sales on low reviews and less competition with high demand and a high search volume on the main keyword consisting graph and must not be seasonal.

Product with high demand, no brand dominancy, high sales volume, low review velocity, ungated category, and product with a good selling price.

The criteria of winning product is
minimal competition
High demand products
Search volume
Sales Velocity
Price range
Profit ratio
Less Reviews
Should not be seasonal product
Easy sourcing and shipping