# Requirement change

Facilities came back to me this morning. Floors 6 to 10 are the offices and the queue in the lobby
every morning is embarrassing, so we are making **lift 3 an express**.

From now on lift 3 stops at the **lobby (floor 1) and floors 6 to 10 only**. It does not stop at 2,
3, 4 or 5 at all.

What I need to be true:

- A hall call from floors 2 to 5 must **never** be answered by lift 3. Somebody on floor 3 who gets
  told "lift 3" and then watches it sail past is worse than waiting.
- Lift 3 still takes hall calls for the lobby and for 6 to 10, and it should still be the one the
  dispatcher picks when it is the best choice — we have not demoted it, we have specialised it.
- Somebody who is standing inside lift 3 and presses 4 has asked for something the lift cannot do.
  Refuse it the same way you refuse any impossible request — the button should not light up and
  nothing should be recorded.
- Lifts 1 and 2 are unchanged: they stop everywhere.
- If lifts 1 and 2 are both out of service, a call from floor 3 simply cannot be answered. Say so
  the way you already say "no lift can reach that floor" — do not quietly hand it to lift 3.

Nothing else changes: the same dispatch rule, the same direction order, the same capacity, the same
one-floor-per-step clock. Lift 3's own route between the floors it does serve is exactly as it was.
