After the two Dodge brothers died, the families couldn't run the company. They sold to some investors that had no idea how to run it. Walter P was in the right place at the right time. The Dodge Brothers cars were well built and had a good customer base. The Maxwells were excellent cars but Flanders had overextended his credit and the post WWI recession busted him. This put Walter P in a very good position when he made those purchases. The Maxwell manufacturing was realigned to be the Plymouth manufacturing soon after. The Dodge Hamtramck plant was well set up and adaptable so it was a big part of the Chrysler & Dodge manufacturing. Chrysler made a few mistakes with the Airflow designs but overall, they had a well rounded group of products that wasn't far off from Alfred P Sloan's GM operation.
Ford stuck with improving the product more than offering more different styles of product so they still had a good corner on the triangle. Ford didn't offer a new line of product till 1939 with the Mercury division.