I'm not sure about Microsoft specifically, but at other companies I've worked at (including the federal government) a level number is somewhat standardized across all roles, not just engineering.

So that means an entry level engineer would start at a higher level than a senior secretary, or whatever the case is.

I've noticed that a lot of US organizations love to use "levels", but coming from the outside it's borderline impossible to know what those levels mean. We have IC levels, and I'm sure I'm on some level, but have zero clue as to what the level may be or mean.

In cases like this where you just have payment guidelines for a level 52, you might as well not know. What's level 52? Is that an intern or senior management?

Not sure if there's an actual reason. But 59 is the actual starting level that matters for software developers.