Wikipedia
The expression cart before the horse is an idiom or proverb used to suggest something is done contrary to a conventional or culturally expected order or relationship. A cart is a vehicle which is ordinarily pulled by a horse, so to put the cart before the horse is an analogy for doing things in the wrong order. The figure of speech means doing things the wrong way round or with the wrong emphasis. The idiom is about confusing cause and effect.
The meaning of the phrase is based on the assumption that a horse usually pulls a cart although there are some examples of vehicles pushed by horses in 19th-century Germany and early 20th-century France.
Usage examples of "cart before the horse".
You're not only putting the cart before the horse, you haven't got cart or horse yet.
True enough all of that is, true as death, but you've set the cart before the horse for the rest of it, Wind Rider.
True enough all of that is, true as death, but youve set the cart before the horse for the rest of it, Wind Rider.