is it true the higher your grade the harder to get a decent grade? and.. someone must get the lowest possible grade even with a decent performance?

I work in one of the Ministries. Yes, I have heard of B+ (but not B-)

Basically, there I have come across C, C+, B, B+, A (very seldom, usually only for scholars). I suppose there is D too, but I am not sure.

It's all inside your SAR forms for all civil servants. It stated: A, B+, B, C+, C, D, E. C is base (good performance) for all grades. No minuses... I suspect there might be C- in internal HR records, but at least it's not official.

Different agencies/schemes have different remuneration packages e.g. benefits-in-kind, PI, MI etc and use different shapes for bell-curves. Even among ministries may vary.

It's meaningless to compare just one of the many components e.g. PB. Most important is whether you enjoy what you're doing e.g. job satisfaction, soft progression etc that in turn indirectly influence your ultimate CEP.

anyone got D or E before?

It means time to get out of here. Probably none would stay long enough to answer it.

no i think someone has to be assigned D or E according to my understanding. that's what bell curve is meant for

no need to allocate D and below... Unless it is meant to penalise the officer.

What does E stands for? Does it imply no promotion in years to come?
What is the difference between D n E? They are all condemned?

I'm with the ministry got 4 yrs...am MX12... I've been gettin B grades every yr...ur cep will also determine ur bonus payout... As in the number of mths... Even with 4Bs, they are not promotin me... In a case of good performance grade and low cep... Wat nonsense really ?!

There is no contradiction here. You perform well every year....and thus your boss is rewarding you with a B grade. This will translate to good performance bonus.

However, your CEP (or potential) is low. This could be attributed to your less than stellar University results or other factors. CEP is the main determinant for promotion and advancement in the civil service. Judging by the way you write, it is not hard to see why you did not do well in your studies.