A visible watermark on your photos distracts from the impact a non-watermarked photo might have and may discourage people from using it. However, the real problem arises when the photo is actually licensed to a customer. Customers are only interested in using un-watermarked photos on their websites. When someone else sees the photo, and decides they would like to use it, they can easily copy and paste it to their own site.
Imatag offers photographers a better way to protect their images.