How does an E6 have 6 service stripes?

Photoshop!

I retired as SSG with 22 years in I could stay in because my job was needed and I volunteered to deploy and then retire.

Personally, Stripes (to me) doesn't mean experience nor expertise. I've seen Great/Experienced Soldiers who retired as an E4 with some demoted at some point and some never promoted above E4 and some reenter the military at a lower rank for one reason or another.

Just a little personal feedback... :-))

Some, like my MOS just don’t really promote. You either go warrant or hope to become one of the unicorns that makes E7.

The individual in question could have had several breaks in service, all totaling up to 18 years. I was in for 16 yrs total and had 5.

Because has not been recommended for promotion to SFC/E'7. Promotions solely based on seniority, they are based on the needs of the Army of that soldiers particular military occupational specialty

I have retired after 21 years SSG my unit didn't want me to leave however I felt that it was time.

I’ve got 7 and am a retired SSG E-6 from the ARNG. Not uncommon at all particularly in a RESERVE component where making E-7 might mean driving halfway across the state to a weekend drill all for an extra hundred dollars a month drill pay and an extra $50 a month on retirement!

I retired as a Ssg. I never had article 15. A lot of it has to do with MOS. I spent 12 1/2 years as E-5 because my job was a dead-end MOS. The cut off was 998 and it was hard to get there. Also when I had that MOS I saw 4 people that were Ssg in that MOS.

Yes, I have 6 service stripes as a retired Staff Sergeant with 20 years of honorable service. Unfortunately, NCOERs require Among the Best on all blocks to possibly advance. When rating schemes are based on personal opinions, and not on potential, many NCOs don't advance.