The pipe is sloping down! What could be the problem? This pipe may end up performing ok but there could be issues. Lets just ignore the codes and proper drop per foot. Home inspection, by definition is not technically exhaustive and we don’t report on code in our reports in Louisiana. It’s the law. So just think of what might happen inside this PVC drain pipe that has an over exaggerated slope. The liquid would run fast. The solids might not be able to keep up with the liquid and sit on the bottom of the pipe. I’m not saying it will happen but it could. On a home inspection, we have to cover our own butt (CYA) so I wrote up this pipe in my report but explained that might function fine.