At the end of the day, cryptocurrency miner manufacturers are selling money printing machines. A well-funded profit maximizing entity is only going to sell a money printing machine for more money than they expect they could get it to print themselves. The buyer needs to understand why the manufacturer is selling the units instead of keeping them for themselves.
Manufacturers that sell ASICs to the public, like Bitmain, tend to be less exposed than consumers to things like ASIC hardforks. Using Sia as an example, we estimate it cost Bitmain less than $10 million to bring the A3 to market. Within 8 minutes of announcing the A3, Bitmain already had more than $20 million in sales for the hardware they spent $10 million designing and manufacturing. Before any of the miners had made any returns for customers, Bitmain had recovered their full initial investment and more.