A large number of small shards is not always the solution, as it can affect the relevance of the search results. In the context of search queries, the relevance score is calculated within the context of a shard. The relative frequencies of documents are calculated within the context of each shard and not across all shards. This is why the number of shards can affect the overall scores observed for a query. In particular, having too many shards to address the future scalability problem is not a solution.