I think what Kurz is trying to say is the factory hose looks like this stuff.
Corrugated PVC hose
I don't know why, but I have never liked the look of this stuff. Seems like it could easily crack and leak. Maybe because it reminds me of my home vacuum hose that cracks and leaks.
The issue with drain hose is the opposite of what pressure hose is for. We don't care about pressure inside the hose, which there is none. We care about the hose collapsing from lack of pressure.
I guess that is what corrugated hose is for. It stays open with lack of pressure.
Kurz, for what it is worth, the corrugated hose is corrugated on the OUTSIDE not inside. So you won't need sealant to fill the space.
--Russ