Why does the US Army persist with the rank of SP4?

I was a Sp5 in the '70s. In 2001 I went back in and was given Sgt stripes. A short time later an E-6 slot opened, but I was not qualified until I attended two NCO training schools designed to lead combat sqauds/platoons. I was a Medic and should have been a Sp5 and then Sp6 not an Infantry NCO.

I was in '79 - '82. I was a SP4 most of my time in Germany. When I made SP4, I was made team leader. When a new NCO came in he would be put in charge of my squad until another Sgt rotated out, my Sgt would move to that squad and once again I would be in charge of my squad. When I rotated to Washington on my pprwk read squadleader. It happened to me again when I reached Ft. Lewis. ETS with E4.

"WHY does the US Army persist with the rank of SP4"?
EASY To Answer:
"Because SP-3 Doesn't Pay As Much As The SP-4" .

W.T.F., Ya Couldn't Figure THAT Out Yourself?

When I was in, Corporal stripes were so rare that anyone wearing them were looked upon as someone sort of "special," in a good way. I was prior Navy and E-4's were NCO's (Petty Officer 3rd Class). It was an achievement attained by TIG/TIS and passing a written exam, etc. It was also one of the largest percentage of an enlistee's pay. It did not necessairly denote a leadership role, though it could and did in many MOS's, but it was the MOST junior level of NCO/Petty Officer. They were expected to act, and be more profesional in every sense. It was a good thing, and a good rank to achieve and was far from a "trophy" award. In fact, the status was viewed as one of the best ranks in that dirty jobs were passed down to E-1's thru E-3's; but that is not to say PO3's didn't get down in the dirt either - they were expected to, but more as a lower level supervisor without being expected to be perfect as it was as much a leadersip LEARNING step and rank.
The Army would do well to follow suite. Even in my day, SP4's were still viewed as being "seasoned" soldiers, so why not give that small boost of prestige?

It depends on the individual soldier and the soldiers supervisor. If the Spc4 shows leadership then it is the duty of the supervisor to latterally transfer him or her to Corporal. Not only will the stripes develop confidence but it will instill the desire to improve.

I made rank pretty quick through to e4...
based on merit and time in..
I went to BLC and PLDC with 1st armoered div. leadership course... As i remember the
spec was and is the backbone of the army. .

No lateral they say in the day...
As a medic 91b sp4 i learned mil tech.
load & fire my 16. bived rain or shine.
and worked in hospitals..
11b my hats off to ya ..

Sp4 I get, it's the transition rank between being a private and reaching a level of actual leadership responsibility. I never figured out how as a gunner and 2nd in command of a $2M Abrams tank I was a soft stripe SP5 E5 yet inevitably the soldier that sat at a desk at brigade and did my pay/leave/statement of charges/whatever in a room full of similar clerks was a hard stripe Sgt E5 as were all of the other E5s in the room.

I smell jealousy of the 'Mafia". Laugh if you will but E-4's are as indispensable as E-5's! The Specialist rank in my time pretty much designated a trooper trained in a specific MOS that required an ability to make use of all elements of their training and being an added component to the battle space. Combat Engineers are a good example. We had training in a long list of special skills. But in the end, either a Spec 4 or Corporal, that individual is needed!!

As a specialist I acted as motor sergeant in Korea while on active duty, then transfered to the reserves and was acting motor sergeant several times as well when the current motor sergeant retired. This was because the points for my MOS were staying at 798, and that was pretty much an unobtainable total.
I would have been satisfied with Spec 5 the stripes were not as big an issue as the pay, and my COC has put me in the position so I had command authority even without hard stripes.
The specialist grades always sounded like the enlisted equivalent of a WO, subject matter experts, who chose to serve but we're excluded from some of the commissioned officer politics, and responsibilities.
In my opinion these ranks were a good idea, and allowed someone to serve while still becoming the highly trained professional needed for their MOS, but not needed at the front of the formation or in the staff meetings as much.