Unfortunately, when a project takes this long, one of two things usually happens.
They get tired of it, say ,"We've had enough!" and cancel it.
Or they get tired of it, say, 'We've had enough!" and kick it out the door and release it as a buggy mess.

"From our orbital vantage point, we observe an earth without borders, full of peace, beauty and magnificence, and we pray that humanity as a whole can imagine a borderless world as we see it, and strive to live as one in peace."
Astronaut William C. McCool RIP, January 29, 2003 - Space Shuttle Columbia