Why is the search time of a meta-engine usually longer than a traditional search engine?
It requires more time mainly because a meta-search engine must wait for results to arrive from all the queried sources before they can be processed and ranked. Whereas, results of a traditional search engine are stored in databases of their servers and page rank is often pre-determined, making retrieval time much quicker. Therefore, it can be said that meta-search engines are only as fast as the search engines and/or directory they search.
