What is SQL Server filtered execution plan behavior under parameterization?

Filtered execution plans depend heavily on parameter values and may change shape based on sniffing and estimates.

When SQL Server compiles a plan with parameters, it may optimize based on sniffed values, leading to filtered or specialized plans. These plans perform well for one subset of data but poorly for others. Parameterization can lead to plan reuse but also instability when data distribution is skewed. Forced parameterization or OPTIMIZE FOR can mitigate extreme cases.