BISG members respond to the “e-book sales plateau” As part of BISG’s single-question surveys, members responded to “What is behind the plateau in e-book sales?” 20% — “E-books have found their level; the market is saturated for now” 25% — “Current e-readers are too limited in terms of rendering design and illustrations” 55% — “E-reader acquisition has slowed as the market has matured, so the customer base for e-books has slowed as well” 20% – “What plateau?”