I've only been a hiring manager once, and it was for a junior-level position so take that into account.
When I read resumes, accomplishments meant next to nothing to me. I was looking for capabilities.
Your EC2 example is probably an exception to what I'm about to say because EC2 is very well known and you can quantify the difference you made in real dollars. But, 99% of the time I have no frame of reference and therefore no way to evaluate claimed accomplishments on a resume.
Oh, you managed accounts totaling $24MM in accrued receivables annually? Sounds impressive, but what if every one of your peers were managing $30–40MM and you were well known to be a slacker? Etc.
It's much more useful to me to know what classes of problem you can solve and which tools / techniques / technologies you're proficient with toward solving them. Descriptive statistics do very little for me.
> and you were well known to be a slacker? > what classes of problem
If people are going to lie on their resume there isn't a whole lot of anything you can do to fix that at the resume evaluation level. So many resumes have 100x skills where they say they know some language because they happen to walk by a room where someone might have been looking at the wikipedia page describing someone who might have used the language once accidentally.
If you can't relate the impact / accomplishment of the candidate for your job to your company,then that just speaks to a low quality resume. It should be obvious to any reviewer why what you did is relevant to their interest.
The reason why impact matters is that in some sense it should be theoretically reproducible. "Saved 100s of engineering hours by fixing some nonsense" which if true should speak to someone who can ostensibly save time while also understand the meaning of their work.
> It's much more useful to me to know what classes of problem you can solve
There is somewhat less opportunity to bullshit on what problems you have solved than on what problems you can solve.