Tuning Thread Pool min size

 Hi All,

I m bit confused with self - tune ThreadPool concept. We can modify the minimum Threads count  Ref to : http://edocs.bea.com/wls/docs100/schemaref/security/http.www.bea.com.ns.weblogic.920.domain/types/kerneltype.self-tuning-thread-pool-size-min.html

I had ran the load test with min as 50. While running the test it went upto 88. Now the test is done. no requests are coming to the server, Hope it should shrink to the min pool size. But it is not happening. Why?

Appriciated if Any proper Document link or earlier discussion threads regarding this issue...