As a rule, authors who publish their works on Amazon's platform receive payment for each single download of their book. The board, however, thinks that this system is not that good, as users often abandon books before even finishing a couple of chapters. Moreover, Amazon states that many writers asked the company to improve their payment system to “align payout with the length of books”. Starting July 1, the authors who use Kindle Unlimited and Kindle Owners' Lending Library to publish their works will receive revenue based on the number of pages read.
Basically, the author of a 100 page book which was downloaded 100 times and read from cover to cover by each user will get the same $1,000 as the author of a 200 page book that was also downloaded 100 times but was read only halfway. Also Amazon is going to introduce a system to standardize the page counter across various devices which will take into account the font size and other aspects. Images will be also regarded as a part of the content, so our eBooks are most likely to become brighter pretty soon.
So the question is: how (if ever) these changes will affect the contents of the works? Short stories are often more likely to be downloaded, but on the other hand we all know that an extensive volume is not necessarily an indicator of quality. Some authors may consider it a good idea to include an additional epilogue, art or simply prolong the storyline just to get more money. Personally I think that most of the quality works won't become worse, as this kind of system has worked for centuries in traditional publishing and is most likely to work for Amazon.