pain in the neck

Definitions

annoyance
To describe someone or something that is irritating or bothersome
discourage someone
Advise against engaging in a particular activity or task, cautioning that it will not result in any positive outcome or benefit

Examples of pain in the neck

Sarah has been a pain in the neck lately with all her constant complaining and negative attitude.

This means that Sarah has been causing inconvenience and frustration to others, specifically the speaker, with her persistent complaining and negative outlook.
Dealing with customer complaints is often a real pain in the neck for sales representatives.

This highlights the fact that handling customer complaints can be bothersome and frustrating for sales representatives, who often have to deal with difficult and demanding customers.
My brother's new puppy is an adorable pain in the neck - he's constantly chewing on everything and won't stop barking!

This humorously acknowledges the fact that although the puppy is cute, he is also causing inconvenience and annoyance due to his overzealous chewing and incessant barking.
My boss has been a real pain in the neck about our team's lack of progress.

In this instance, "pain in the neck" is being utilized to describe someone who is overly critical and demanding, specifically toward the speaker's boss who is frustrated with their team's slow progress.
She's been so fussy lately about everything, it's become a real pain in the neck.

When you say someone is a "pain in the neck," you mean they are causing you a lot of inconvenience or irritation, usually because they are being difficult or demanding. In this example, the speaker is saying that the person they're describing has been very picky and hard to please, which is becoming a major annoyance to them.
My computer just crashed again. Dealing with all these technical issues has been a real pain in the neck.

Here, the speaker is using "pain in the neck" to describe a particular problem, namely the frustration and inconvenience caused by repeated technical difficulties with their computer.
He's always complaining about something or other. I swear, I'm starting to think of him as a human pain in the neck!

This example shows how the expression "pain in the neck" can be used figuratively, as a humorous way of describing someone who seems to be a source of constant hassle or bother.
Cleaning up after her is like picking up after a hurricane. She leaves such a mess, it's a real pain in the neck.

The speaker is saying that the mess this person leaves behind is extremely excessive, making cleanup a major hassle. By comparing it to the aftermath of a hurricane, they're emphasizing just how overwhelming and difficult it can be to deal with.

Conclusion

The idiom "pain in the neck" is commonly used to express annoyance or to discourage someone from a particular action. When someone refers to a person or thing as a "pain in the neck," they are expressing frustration or irritation. Additionally, it can also be used to caution someone against engaging in a specific task or activity, suggesting that it will not lead to a positive outcome.

Origin of "pain in the neck"

The origin of the idiom "pain in the neck" is believed to be a euphemism for a more vulgar expression. The phrase is thought to have originated in the early 20th century as a toned-down version of a more explicit term. The use of body parts to convey annoyance or frustration is common in idiomatic expressions, and "pain in the neck" is just one example of this. Over time, the phrase has become widely used in English-speaking countries to convey irritation or to discourage certain actions. Its origins may be rooted in the idea that neck pain can be particularly bothersome and disruptive, leading to the metaphorical use of the term to describe anything similarly irritating.