When training new units, the second button listed under "Quality:" remains unlocked after starting a new game without first exiting the game.

To duplicate:

1) Start a game as the Tarthans and found a city.

2) Note that the "Experienced" button is available for use.

3) Start a new game as Altar without exiting and found a city.

4) Note that the "Experienced" button remains available for use.

5) Now exit the game and restart.

6) Start a new game as Altar and found a city.

7) Note that the "Experienced" button is now properly unavailable.

I haven't tested it for the "Veteran" or "Elite" buttons, or for the "Quantity:" buttons, but this may apply to them as well.