Pretty amusing. This manga almost got axed due poor sales after first volume. And now look at it. Anime.
As stated in the afterwords of the following volumes, the author meant that as a bit of a joke, playing on his own worries. But people took it to heart and responded by buying a lot of copies.
To my knowledge, there's no public information on how well it was actually selling or how well-rated it actually was at the time, so it's tough to judge how founded those fears of his were.