"interest faded" is a correct and usable phrase in written English.
It is often used to describe how someone's enthusiasm or curiosity has decreased. For example: After the initial enthusiasm about the project faded, the team members had a hard time staying motivated.
So why has interest faded?
Just 24 hours later, its interest faded.
Then interest faded; France has been trying to sell 50 million doses.
Although newspapers across the region splashed it over their front pages, and TV talk shows rattled on into the wee hours parsing the implications, interest faded quickly.
After the death in August 1997 of Diana, Princess of Wales, who had made land mine clearance her special charity, interest faded.
But here he found his interest fading once again.
It might be a simple example of the "pendulum effect", a political example of the regression toward the mean phenomenon; after an initial burst of excitement about change, interest fades.
Mr. Leno's "Tonight Show" return was heavily promoted during the Winter Olympics on NBC last month, but once the initial interest fades the real competition will begin, as NBC and CBS find out whether "The Tonight Show" can return to the No. 1 spot among total viewers -- as if a certain redheaded comedian had never been there.
[C10.] Interest Fades in Bayer Unit Investors began bidding up the shares of Bayer last month as soon as the company abandoned the idea that it could merge its relatively small and weak pharmaceutical unit with another drug maker and retain control of the new company.
So no matter how innovative your research, with the possible exception of making alien contact or cold fusion, you will be in the news for only a very short while before interest fades.
