off topic: combined output of concurrent processes

[Amadeus W.M.]

> 
> [egreshko at meimei test]$ grep ^A out | wc
>      97      97     582
> [egreshko at meimei test]$ grep ^B out | wc
>      94      94     564
> [egreshko at meimei test]$ grep ^C out | wc
>      96      96     576
> 


I replicated this and indeed I don't get 100 lines of As, Bs and Cs. 
That's a new problem. Why don't I get all? Shouldn't all 300 echos have 
been launched when the script completes? And if the script has completed 
and there are echos running in the background, they should complete, no?

I put a "wait" at the end of the script to wait for the completion of the 
echos, but I still get fewer lines than 100 per A, B, C.

This is aggravating. So not all echos get executed (why?), yet I still 
don't see the output mingled.