What are Style Tiles?
Style Tiles are created as a way to communicate visual direction and gauge your preferences for the overall tone as well as the individual elements found within the groups of elements as shown as typography, colors, buttons, and textures. Please feel free to comment on any particular elements across all three of the Style Tiles in terms of preference
The elements/tiles you indicate are your preference help give the visual designer a good indication of what to combine in the next iteration working towards one visual language for the entire product.
Also you can refer to this for additional language around how style tiles are used: http://styletil.es/