Why does vaping taste weaker the more you vape? Is it taste fatigue or a product issue?

http://oss-relx-app.relxtech.com/CommunityVideo/20201511181539_app%E5%B0%8F%E7%9F%A5%E8%AF%86%E6%A8%A1%E6%9D%BF_1.mp4 Why do I feel the flavor gets weaker and weaker the more I vape? As the saying goes, if you live long in an orchid room, you stop noticin