Native Japanese speakers rarely say "domo arigato" in everyday casual or professional interactions because it occupies an awkward middle ground in terms of politeness and register. In casual daily speech, people prefer the quick and simple "domo" or "arigato." Conversely, in polite, business, or formal situations, social etiquette strictly demands the complete, respectful phrase "domo arigato gozaimasu." Dropping the final polite suffix sounds incomplete or overly theatrical to native ears.