Why are temporary tables not removed from tempdb in SQL Server?

Question

I have created one stored procedure with 7 temporary tables and each temp table is dropped at the end of their own work.

I am calling the SP from one web service and

Answer 1

This can occur in case if you have used many Temp tables and you have some Error in between of Your sp and your drop statement could not executed.
So its always best practice to use

IF object_id('tempdb..#TableName') IS NOT NULL DROP TABLE #TableName

in start of SP.