New Purple Phalaenopsis

I bought this new plant today at a chinese grocery store in my neighborhood. One of the leaf is sunburned but the flowers look really nice. Many of the roots are rotted or dead, so I had to cut them off. I'm always worried that the roots I cut off are important. There were some healthy roots but not many of them to at least support the flowers. Paid $15 but not sure if I should've bought it.