I'm looking for a preferably short idiomatic verb phrase meaning "fail, through poor execution, to be rewarded by an unusually easy opportunity."
An example scenario would be, the hottest girl in school having a crush on some plain, unpopular guy who goes on to fumble a date with her, losing her interest.
Keep in mind, you can still ____________, so it doesn't mean any hopeless dimwit could win this.
Some I've considered:
"Miss the boat" suggests a loss by inaction rather than ineffective action, and also doesn't express the luckiness of the opportunity.
"Drop the ball" perfectly expresses the ineffectiveness of the action, but again fails to express the luckiness of the opportunity.
"Let X slip through your fingers" is a little long, doesn't fit the sentence structure without providing X, and also doesn't strongly suggest that what you've let slip was unusually opportune.
I thought of "throw away a good hand" as coming fairly close, except that (i) it could suggest that the opportunity was intentionally rejected or not taken at all, and (ii) in some card games, this is actually an advantageous strategy in some situations, which is not the intent.