WSDL is a core part of WebServices standard, but has become more of multi-headed monster. The problem — In order to be generic enough for a refrigerator to find and bind to a WebService advertised by a microwave, the WSDL specification has become incomprehensible and is now touching the 140-page mark.
Probably, the chair leaders and the participants forgot to read the charter. I quote, “Focus must be put on simplicity, modularity and decentralization.”
No wonder, alternatives (SSDL, SMEX-D, NSDL etc.) are springing up and Tim Bray (co-author of the original XML 1.0 spec.) is already calling it quits on WSDL.