If you do not remove enough metal to create a new edge, you will leave some of the dull edge in place. A dull blade (or a blade with dull spots or nicks) will reflect light from the very edge of the blade. A razor sharp knife edge will not show "bright spots" when you hold it blade up under a bright light. You will need to remove enough material from the sides of the bevel so that the edge stops reflecting light.
Frequently, our recommendation for beginning sharpeners is to start with diamond stones as their strengths make them ideal to build a sharpening toolkit around. Diamond stones are low maintenance and durable, lasting many years with only occasional cleaning. They are among the fastest stones to use making them time efficient. Diamond grit will handle even very hard steels, and diamond stones can be used for flattening waterstones. All these things make diamond stones a practical foundation for your sharpening toolkit.
I love sharing information, please never hesitate to comment if you are stuck or need some advice on water stones. Speaking of that, if you have more than one stone, start with the coarse and end with the fine stones and repeat the process on each stone. However, you only need P4 pressure on that first stone, the the Raising of the Burr Pressure. After that, keep it moderate to light.
My first set of sharpening stones so I have nothing to compare them to. For $50, though, great price to get into the world of sharpening. Stones are great and easy to use. Was able to put hair shaving edges on knives. Took a couple of knives to feel comfortable and better with the process and how to sharpen, but the stones you get work great. Here's the secret though. Get the green leather stoping block as well. As great as the stone are, I have found that stroping the knife after the fact is what really brings out that razor edge. And after using the knife, stroping it again, will restore and keep it razor sharp. Hope you enjoy it as much as I am.