Your maximum keyword spend is an arbitrary maximum amount of money or budget you are willing to spend on a keyword, if there are no sales before you then drop your bid to its minimum.
For Example:
If I’m selling a product that costs $20 and it costs me $21 to get a sale,
then this doesn’t make sense because I’m losing at least $1 for every sale, and not to mention whatever I have to pay to Amazon.
Examples
Seller's intention
Selling Price
Max. Keyword Spend ($)
I am launching a product and want to be aggressive.
$20
$20
I want to have a maintenance campaign with this product.
My product is ranked with a lot of reviews, which means I don’t need to be too aggressive.
profit of this product that I’m selling for $20
How much my dollar profit is on the product?
$10
Regardless of the number of clicks a Keyword or Target has, or even the minimum action clicks, as long as the Max Keyword Spend is reached, the bid is dropped immediately.