Hello @vinodkumar_Mallikarj,
In the first query, it was a case of Covered Query. The query was served by the index alone. That means, the index doesn’t have to lookup the documents for any additional details. The query filter and the projection are covered by the index fields.
Here the FETCH stage is added additionally and it is returning the same records
This is because the query had to fetch additional data, the field teams, from the document. The trip to access the document is your additional time and the FETCH stage in the query plan.