虎头蛇尾 (虎頭蛇尾) hǔ tóu shé wěi

hǔ tóu shé wěi set phrase a tiger's head and snake's tail; a noble start but weak finish
Domain: Idiom 成语
Notes: (CC-CEDICT '虎頭蛇尾'; Guoyu '虎頭蛇尾')