Here are the fun facts and statistics.
Let's say you are a fresh PhD , joined as a T3, and you joined 3M in the hopes of doing great science and technology. Let's say you stay in the technical track for your career in 3M. Let's do some projection for your career track.
Unless you make multiple million dollar products for the company, get credit for it and most importantly your boss and bosses boss likes you, you will end your career at the T4A level. Of course these days you are likely to get laid off after a certain age, let's say roughly 50 or so.
This is what happens to the majority of folks in the technical track. A grand total of 2 career promotions (T3 to T4 and then T4A) in a long 25 to 35 year career in 3M ( if you can still have a job that long in the first place).
Meanwhile let's see what happens if you decide to join the management track. Most people join management track after getting to a T4, after realizing that they are "management material" (i.e. not meant to work in the lab doing hands on work ) and are ready to kiss their bosses rear side at every opportunity.
Let's do a career projection here. In most cases going from a supervisor (equivalent to T4) to a Technical manager (equivalent to a T5) takes 5 to 8 years. Thus in 8 to 10 years, after PhD, you are very likely to assume a position that 80 percent of technical track employees can never make in their entire career. This is almost guaranteed to happen. There is something magical or divine thing that happens once you join management track. Immediately you become "high potential". Note that this Technical Manager position also allows you the coveted stock options and RSUs.
If one is good in keeping bosses happy, then typically you can end your career at the Director level ( equivalent to T6 level). This is something that maybe 4 or 5 percent technical folks can ever dream to achieve!
Still interested in a technical career in 3M ???? Join and have fun.