There was bound to be some drop off. “The Fame” era is of the like that only come around once in a generation. Being an 80′s kid i can tell you she blew Madonna out of the water and easily made the best pop in 20+ years.
Born This Way as an album is “good” but only “OK” compared to The Fame and The Fame monster. Honestly I think her biggest mistakes in the BTW era was the songs she choose to promote on the album. Edge Of Glory, Mary the Night, Without You? These are very average songs that are overly sentimental. The better songs you can find fan made videos of. Songs which Gaga did nothing to promote herself. She had number 1′s on the album but just didnt release a singe or make videos for them “Bloody Mary” and “Fashion of His Love” two examples.
Basically what she promotes was what only avid Little Monsters would like and nobody else would. For that, she lost the broad appeal and fan base that her older stuff gave her.
But its only one era out of two for Gaga and many yet to come.