A recompilation is the same process as a compilation, just executed again. If the database structure or data change significantly, a recompilation is required to create a new query execution plan that will be optimal for the new database state and ensure better procedure performance.

What is a SQL recompilation?

If a database undergoes significant changes to its data or structure, recompiling a procedure updates and optimizes the procedure's query plan for those changes. ... When SQL Server executes procedures, any parameter values that are used by the procedure when it compiles are included as part of generating the query plan.

What causes SQL Recompilations?

SQL Server Recompilation Reasons

A recompile of an execution plan could be due to database level configuration changes, schema changes, index changes, etc.