I want my trigger to prevent deletion of Account records, the code doesn't show any error but my Account records are still being deleted? here is my code

trigger PreventAccountDelete on Account(before delete){ for(Account a :[select Id from Account where Id IN:Trigger.old]) { System.debug('Cant delete'); }

}

I want my trigger to prevent deletion of Account records, the code doesn't show any error but my Account records are still being deleted? here is my code

trigger PreventAccountDelete on Account(before delete){
    for(Account a :[select Id from Account where Id IN:Trigger.old])
    {
        System.debug('Cant delete');
    }
    
}