I really like this eggcorn. It makes sense: squid live in water and I imagine living in water makes you damp. I’m not sure why damp squid are seen as failures or as disappointing; that seems rather unfair on them.
The phrase is actually damp squib. It is usually considered British English.
A damp squib is a situation or event which is less impressive, exciting or popular than expected.
A squib is a type of firework or firecracker. Small explosives used in the military and in industry are also called squibs. If a squib gets damp, it won’t go off.
To British readers – I hope your Bonfire Night wasn’t a damp squib. If you are going to see fireworks this weekend, I hope you have a wonderful time! (Fireworks are one of my favourite things.)
Hannah McCall 
[…] words come from and words that often group together. You might recognise the eggcorn in the title: damp squid. It appears in the chapter discussing idiomatic phrases, and the chapter is fascinating (especially […]
LikeLike
That’s interesting, I didn’t know Damp Squib had morphed into Damp Squid……I wonder if a typo or mis-heard conversation started the whole thing?
LikeLike
Yes, it is attributed to people mishearing the original phrase. But I wouldn’t be surprised if sometimes the misunderstanding does stem from typos or autocorrect!
LikeLiked by 1 person
Love the expression. Have never heard it before but must start using it 😊
LikeLiked by 1 person
Ah, that’s what a squib means. I’ve often heard the saying, but didn’t know what in the world a squib was. Interesting. 🙂
LikeLike
I’m glad I could solve that mystery! 🙂
LikeLiked by 1 person