In Shemot 20:23, Hashem commands us not to ascend to the mizbe'ach (sacrificial altar) with stairs for reasons of modesty. However, we learn in Tamid (3, 9) that the Menorah had stairs before it in order for the Kohanim to reach the lights. If stairs are prohibited because of modesty, then it would seem that they would be more of an issue with the Menorah which is much closer to the Kodesh Hakodashim than the mizbe'ach.
How do we resolve this discrepancy?
(On a related note, why aren't stairs prohibited outright?)