Why are there varying waiting periods in connection with Open Access publishing?

The reason why the waiting periods – during which an article is exclusively available through the scientific journal publishing it – vary, is that the period during which research results are to be considered newly published, and thus deemed to have a higher economical value, differs depending on the scientific subject. Thus, the period for which research results within Information and Communication Technology have status as newly published results is shorter than in the Humanities or the Social Sciences, which is why the Open Access publication of ICT articles has a shorter waiting period.