Excellent point.
One could semi - 'excuse' bethesda for not coming out with FO4 in 2013 only because FONV came out in 2010. Thus, it could be said that there is a 5 year gap between titles.
But the truth is that it's a mistake for Bethesda to take more than 5 years to produce quality titles in FO and ES - and I mean from a Business perspective. It's an unnecessary risk.
Some of you will argue that the most important thing is to have a high quality title when released. One cannot dispute such an assertion.
It is, however, a management failure on the part of Bethesda to not have the organizational skills to build and manage development teams that can do such a thing on 5 year schedules.
Hence my repetitive whine on this subject
(I apologize to those of you who are sick of it; I can't blame you for being tired of hearing this. I promise this is the last time I'll say the above. )