The request came from a former co-worker. His employer (a for-profit business) was hosting an event and needed insights from a local with in-depth knowledge on a topic that I have covered in a weekly column for years. I could sense it coming: “I was hoping to pick your brain,” he wrote, before asking me to come to their office 30 minutes from my home office. There might be a couple writing assignments in it for me, he said as he wrapped up the email.

I replied with some resources and an offer to connect him with a trade organization that could be of help, and — I thought — a friendly bit of advice about that dreaded request: to nix it. And I closed by letting him know I'm available on a consulting — read: paid — basis if my expertise was further needed. He didn't reply.

It's such an easy and innocuous request that people throw it out like fishing line. If they drop enough lines, maybe they'll catch something. But what they don't realize is that there may be some unwanted repercussions.

“When someone needs to say no [to a brain picking request] and they feel uncomfortable or that they can't, you can cause damage to the relationship,” said Michelle Tillis Lederman, author of "The 11 Laws of Likability." And that relationship is more important than any individual question, she added.

5 Little Words That Get Many Professionals Hot Under the Collar

But why? Why does the mere phrase get me — and so many others — so worked up? Fellow freelancer and entrepreneur Kristin Luna shares my heated reaction to the request. She has a job that's a dream to many: traveling the world and writing about it. Naturally people will contact her to ask her how they too can have that job. And they often phrase it as a brain-picking.

“Being new to a profession or field and trying to gather intel, I feel like asking someone who's been working in that profession for 15 years to divulge all their secrets is the ultimate offense,” Luna told NBC News BETTER, “because you're implying that my time and schooling and building up my career isn't valuable enough to pay for it.”

If you're asking a question that can be answered with a Google search, well, you shouldn't expect an answer from any busy professional.

Luna also provides consulting services in the tourism industry. “For someone to ask if they can take me out for five dollar coffee when we charge our clients hundreds of dollars an hour — you wouldn't do that to a lawyer or doctor,” she said, “so I don't know why there's this disconnect that the same respect shouldn't be shown to other professions.” That coffee break, by the way, is a different matter when you work in a more traditional environment, she pointed out. “When you're in an office, you're getting paid to be there no matter what, and you can slip out for an hour to take a coffee date,” she said. “But when you're self employed you're literally losing money when you're not working.”

A Conversation That Strikes a Chord and Hits a Nerve

And it's not just the freelance or consulting world where brain picking requests are a bad idea. When I raised the topic among friends it clearly struck a chord. A lactation consultant gets hit with requests for free help every day. A paralegal is also bombarded. As is a coffee shop owner and a nurse I heard from. And Christine Vaughn, an event planner in Louisville, Kentucky, gets frustrated with the barrage of requests for her — free — counsel on planning events.

“I have worked hard to get where I am and figure it out as I go,” she said. “I know I am damn good at it and there is a need for my skill set.”

How to Push Back When You Need To

But telling people no — especially as a woman — is fraught with discomfort. “It offends me because I have put a lot of time, money, energy, blood, sweat and tears into what I do and what I know,” Vaughn added. “These are the things I tell myself when I feel guilty for not just sharing all my knowledge.”

While most men I heard from when I reached out to friends said they didn't mind the request, every woman who responded did. “I think it's harder for women and it's harder to say no and we come across as a b---- if we don't oblige,” Luna said. “That's something I struggle with all the time as an entrepreneur. I really hate that we have to play so delicately in the business space when we're female.”

Now we're not all just a bunch of Scrooges. Requests for help from friends are gladly taken. I'm always happy for the chance to pay forward or pay back the many times I've asked friends for advice that they freely gave. I've been the beneficiary of many generous people in my career and my life and am grateful to all of them. (I've also cringed more than once since starting this article thinking about times I've made my own faux pas!)

The rub comes when a passing acquaintance or stranger wants to replace their own due diligence with a “hey, can I pick your brain” message. “Ninety percent of my requests these days come through Linked In or someone who found my site and a lot of it comes down to laziness” Luna said.

Or when the ask entails more than a quick response, said a web designer friend. “When it takes more than five minutes … you move from friendly question to a subject matter expert territory to billable hours territory.”

So what's a person to do if they genuinely want help from someone and don't want to damage the relationship? Lederman had some tips. There are several ways to ask for help that take the pressure off, she said.

You can give them a way to opt out. That could be as simple as “I know you're busy; if you have time ...”.

You can make it easy — give them options other than spending a chunk of time, like recommending an online resource — and make it convenient. As opposed to the former co-worker who wanted me to spend an hour on the road just getting to and from the appointment, make it easy for the person to grant your request by letting them choose a place and time most convenient for them.

You can let them know what's in it for them. That's fairly easy when you're a journalist asking an expert in their field to be featured in a national publication but easier said than done in other cases.

That's fairly easy when you're a journalist asking an expert in their field to be featured in a national publication but easier said than done in other cases. And then there's the "non ask." (I might call it the big hint.) Say someone wants to open an Airbnb and they know I've been a superhost for years. They could just mention their plans to me, leaving it open. “It's not asking anything of you, you have the option of offering or not,” she said. Depending on who made the non ask I might suggest some resources including my blog or tell them about my consulting service. Or choose to not take the bait. No harm done.

Do your homework before you ask

I would add that it's important to have done your homework first. If you're asking a question that can be answered with a Google search, well, you shouldn't expect an answer from any busy professional. Your request should also be specific.

“I will routinely refuse requests to connect or I'll email back with a simple 'can you be more clear about your request so I can better answer you? '” said Kevin Liu, a restaurateur in Richmond, Virginia.

“If people keep pestering without being clear,” he said, “then I will usually set up a filter so that all their future message go straight to trash.”

While Liu doesn't find it “offensive per se,” he said, “If someone asks to pick my brain, it makes me assume something about them: that they are either clueless, lacking confidence or trying to hide something.”

So before you hit send on that next "pick your brain" request, take a moment and consider what you're asking. Do some homework, figure out what exactly you're asking for, make it easy, give them an out and let them know what's in it for them (and don't forget the good old please and thank you). Sound like too much work? You could always just hire them.

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