why Jquery Requests wait for the previous request Completion

Question

i made this simple web app where i used pagemethods and ajax request using jquery

i Created two Page methods
1- Execute [WAITFOR DELAY '00:00:10'] on sql connection
2- Return "Hello World" String .

the problem is when i request Method(1) then Request Method(2)
The return Of method(2) waits for The first Request To Finish Then Return .

is that logical or am i doing Something wrong ?!

i'm using vs2010 with iis7 on Windows7