During one testing session at the beach I was reminded why I prefer hammering smaller search areas, instead of walking long distances at the beach trying to cover more ground.
You can miss targets using a tight search pattern at the beach, especially if you only search the same areas from the same direction all the time.
This is the reason I always double back over any area I recover something good at, searching the same area from a different direction.
You will be surprised how many signals you get searching the same area from a different direction, both iron and target masking are to blame for leaving stuff behind.
There are many simple reasons why iron objects were missed on the first careful search of an area.
For example, large iron objects masking smaller pieces of iron, large non ferrous (Iron) objects masking smaller non ferrous targets.
Targets caught in the corroding iron halo, also targets located on edge that can only be detected when your search coil is swept from one direction.
They could be targets on the edge of detection range, perhaps targets not detected at first but moved when you dug a target close by.
So many different reasons for targets not detected on the first sweep of an area, but often detected on a second search from a different direction.
Every time I detect targets on a second sweep from a different direction over an area, it reminds me of the saying " They cannot get it all" used by beach hunters.
I often go back and cover productive areas from different directions, every year I recover several pieces of gold jewelry I would otherwise had left behind for the next searcher.
This is one of the reasons I often search ground I have already covered from a different direction.
The beautiful antique 18 K amethyst ring found a few years ago, was missed on the first search, but not on the second sweep of the same area.
I believe you will agree detecting targets other beach hunters missed is great, detecting targets you miss is even better.