He's always promising to help, but it's all talk and no action.
showy but ineffective
Frequency:
60
%
Her presentation was very showy, but ultimately ineffective.
superficial charm
Frequency:
50
%
He had a superficial charm that wore off quickly.
flashy but unreliable
Frequency:
45
%
The new sports car looked flashy, but turned out to be unreliable.
Idiomatic Expressions for all show and no go
Phrase: all show and no go
Meaning: Someone or something that appears impressive or promising but lacks substance or the ability to perform effectively.
Usage: The new sports car looked great, but turned out to be all show and no go when it came to performance.