I was surprised to see my result yesterday. I to...

I was surprised to see my result yesterday. I took my exam on 28th Sep and I got 6 band in speaking . Examiner who took my speaking test was giving me signs during my test to speak less and other signals and I took it as positve however got surprise to see that I got 6 Band in speaking . I got 6 in speaking when I took my exam first time around 10 years ago when my speaking skills and confidece used to be low. and I already took test 4 times in Australia and have never got less than 7 in speaking and took test on 6 July in same centre and got 7.5 in speaking . I donot understand how ones speaking skill can go low just in 3 months when we improve each day.