Daraz is an online based store where you will find different kinds of goods based on Bangladesh.
They have their own official store from where you can buy things. Or you can buy from other shops within their website or app.
If you buy from their official store they'll usually provide good products. But they don't monitor the goods of other shops. Sometimes the products of other shops can't meet the demands of customers. And sometimes they themselves provide cracked or duplicate products.
Lastly, Bangladesh is a developing country. The demands of online based service are increasing day by day. But Daraz is exploiting this opportunity. Hope they'll do better in near future.