In games that have video ads, the availability of video ads can be determined by several factors:
Operating system - Most video ad providers do not support Amazon, so video features are frequently not available on Kindle devices.
Daily View Restriction - Most games only allow you to watch a certain number of videos per day; some also limit the intervals between. You should usually see a timer showing you when you can watch videos again.
Location - Some providers limit videos by location, or only cater to certain regions.
Devices and Other Data - Some third parties will collect usage data from views (see our data privacy statement in the game); it is possible that they may limit which videos are shown to certain users based on this.