“No contest” clause is included in attempt to avoid challenges, but state laws vary.
The outcome of a challenge to an estate isn’t guaranteed and could backfire, according to the Wills, Trusts & Estates Prof Blog in “Take It or Leave It: The Perilous Decision of Whether to Violate a No Contest Clause.”
Sometimes when a person challenges a no contest clause and loses the challenge, courts will refuse to enforce the clause. Sometimes when a person challenges a no contest clause and wins the challenge, the court will enforce the clause anyway.
The difference between the two extremes is a matter of individual state law and what exactly is being challenged.
There are different rules in every state.
An estate planning attorney can advise you on wisdom of filing a challenge and the potential outcomes.