[spaceballbat]

The jump from junior to senior means you can self start and have created enough of a network to seek out help. Junior used to be a 1-3 year training period. Senior to principal means you have signififcant positive impact across the company: upper management relies on you to define the roadmap. Most people hang out in ‘senior’ for their entire careers because they never have that drive to stand out. Thats why there are titles like “staff” and “senior staff” to promote people who don’t have what it takes to get to principal.

[Ekaros]

I always wondered why don't we have just developer level. That is for those with say 5-7 years of experience. That are skilled enough to do their bit on their own, but might not yet fully see the big picture on whole application scale for whole thing...

Straight from junior to senior just feels weird jump. Junior and Senior sound like adjectives to me. Qualifiers. And there should be some middle point in between where bulk of the workforce doing the actual job should be.

[dagmx]

A lot of companies do have levels. See http://www.levels.fyi