Not half as
Definition 1 of 1
Pro Tip 1/3Comparative Strength
Represents a strong comparison, indicating that something falls significantly short of the standard. 
His performance wasn't half as memorable as last year's lead.
Pro Tip 2/3Expectation Versus Reality
Use it to express that reality did not meet someone's expectations or hopes. 
The movie was not half as exciting as the trailer suggested.
Pro Tip 3/3Subtle Disappointment
It can convey a sense of disappointment without being overly harsh or direct. 
This cake is not half as tasty as the one you made last time.