Problems such as these are usually a management failure. The design of individual components are often owned by a particular person or small group. They take responsibility for the design and testing. If one person owns the sump and another person owns the exhaust pipe, their work needs to be coordinated in such a way that the finished product meets all its goals. It wouldn’t be a surprise to find out that the exhaust engineer had to re-route the pipe in order to resolve some other clash and they ran out of time to fix the new problem before mass production had to start. Making complex machinery is difficult.