That's better than seeing man-years go into features that get deployed. I witnessed one successful control system company spin up a team of new hotshot UI engineers, all right out of the best schools. After months of work the team "updated" the product. Withing hours the call center was hit with hundreds of "You changed the g-dam menus!! Put them back NOW!!".
The trick is to squeeze your long-term UI project in the same update as some routine security fixes. Then the clients are forced to learn the new system.