Since we really don't know what they see, it's hard to say why they hit some colors. Then why on one day they really take one color and at the same place the next day they take another because there is clouds and the day before it was sunny. It all can make a difference for sure.

However I do believe that confidence is the biggest part because you will try it longer and harder expecting it to work. Even so I still think color, size (profile size) and movement (slow or fast or in between) all can be a key.

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