Originally Posted by Damius
Really, have they ever gave an explanation why it is that way?
Well, since it is a jinx, it is a situation where people are seeing a supernatural relation between Thing X and Thing Y. So, it may be rather difficult to offer a non-supernatural explanation for the matter. But I try, anyway.
(There was also a jinx on Kirara 4-koma manga: a Kirara 4-koma manga which had a drama CD cannot have its anime version. But the jinx was broken with Acchi Kocchi
's having its anime version.)
Except some very popular/prestigious titles, basically, media franchise-wise, 4-koma manga have been not big, in comparison with standard-format manga. So, many 4-koma manga didn't/couldn't cross over from their original medium to other forms, especially to anime.
Even if a 4-koma manga has its CD drama, usually it is something like an 'I want a motorcar, but I cannot afford a limousine and a chauffeur, so I buy a minicar' thing.
Another factor which can be taken into account is a matter of the sub-genre 'moé 4-koma'. So-called moé 4-koma are recent 4-koma manga which have otack
y styles and contents and are aimed at younger otacky readers. As a matter of course, moé 4-koma have more chances to cross over from their original medium to other forms than non-moé 4-koma. But non-Kirara Hōbunsha 4-koma manga are non-moé 4-koma, non-otacky 4 koma, 'family' 4-koma, 'fundamentalist' 4-koma, 'old school' 4-koma, and the like. So, non-Kirara Hōbunsha 4-koma manga have less chances, and people tend to think that to have a drama CD is probably the limit of a non-moé 4-koma's capacity, even if it is so-so popular. Therefore, people also tend to think that there is such a jinx as that.
In fact, Dr Akira
, Radical Hospital
, Love Lab
and Honey Café
are non-Kirara Hōbunsha 4-koma manga and have drama CDs, but they don't/cannot cross over from their original medium to anime.