Many people starting out reading what others have done in finding old coins, jewelry, etc. Then they start thinking that it's like a recipe, if I do the exact same thing, I will get the same results. They even see a pic of great finds and say "I want the same detector he has". They don't see the many hours the person had to research where to dig, or even the fact he had to "learn his machine" or "dig loads of junk to get an idea what NOT to dig". All they do is trade machines hoping to think they have the "deepest" machine and that it's the best one that IDs junk and treasure. Most of my best finds have been no more than 6", and many around 4". It's not about depth, IMO. It's about skill and perseverance as well.
People need to realize that it's a "metal detector" and it's going to find "metal". I wish there were as many coins in the ground as pull tabs. But that's not the real world in most hunting places.