This has been a memorable year for Lani Hay: She won a prestigious national women’s entrepreneurship award and her defense contracting firm brought in $80 million in new contracts, equal to four years of revenue.

Even as she expanded her payroll by some 100 people in the past year, Hay ran into a speed bump when she tried to recruit a chief operating officer, her No. 2 position.

She hired one, then a second and a third. None of them lasted long, but they taught Hay some important lessons.

All three were males, and Hay, founder and chief executive of Vienna-based Lanmark Technology, says she’s discovering that not every man is comfortable working with not one but two alpha female ex-military executives.

“I don’t want to let anyone in the corporate culture who’s going to disrupt the culture and isn’t a good fit,” said Hay. “The CEO is really the person who owns the culture of the company … and hires people that reflect what I want in the culture.”

Like many employers grappling with a hire that didn’t go as planned, Hay is taking a step back and trying to figure out what the firm could have done different.

Each of the three men hired as a No. 2 had all the technical expertise required, and the first one came highly recommended by the man who left the job, Hay said. Yet none were comfortable in Lanmark’s “dynamic and fast-paced” culture, as Hay describes it, which is a mix of military rigor and her friendly, open attitude and competitive spirit.

“Fast and dynamic are relative terms, so until someone can get a true understanding of what [Lanmark] considers to be fast paced and dynamic, it’s only their own previous experiences that they’re basing their understanding on when they say they work well in that type of environment,” Hay said. “Too many balls get dropped if you can’t keep up, and I’m trying to assemble a team of committed professionals to catapult [the company] to the next level.”

Much of Lanmark’s hiring comes through military transition assistance programs, or TAPs, though earlier this year, the company also started using Facebook, Twitter and LinkedIn to locate and recruit people. Approximately 85 percent of Lanmark’s 200 staffers have military backgrounds — either they served a tour of duty or they worked for the Defense Department or one of its agencies. About 57 percent are male.

Hay worked as a naval intelligence officer, and retired Col. Laurie Buckhout came on board in August 2010 as vice president.

Hay, the daughter of Vietnamese immigrants in suburban Virginia, said she grew up believing women could do anything. “I didn’t even realize there were barriers to women,” she said, until she learned she couldn’t join the Navy’s Blue Angels because women were still excluded from combat roles.

“I used to approach these obstacles with a full frontal attack. I learned that is not necessarily the smartest way,” she said, noting she still keeps the book “The Art of War” by Sun Tzu on her nightstand as a reminder of how to tackle issues strategically and tactically.

“As I built my company, I hired the best people I could afford, not necessarily the best people,” said Hay, who last month was named one of 10 of Ernst & Young’s Entrepreneurial Winning Women. Now that’s shifted, she said, and Lanmark offers competitive pay, several incentive and merit bonus programs, and tuition reimbursement.

Yet when the first COO came on board, “there were red flags going off there, and no one was talking about it,” she recalled. Several staffers kept quiet about their concerns and complaints, thinking they were the only one. So after Hay terminated him, she brought together her corporate staff, explained why he hadn’t worked out and encouraged them to provide feedback more freely.

They spoke out more readily after the next two recruits came on, which meant one worked for Lanmark for only a few weeks.

Hiring people who fit in the culture starts with a clear message on core values. “Four core values are good. I don’t recommend 10,” said Michelle Roccia, senior vice president for corporate organizational development for Winter Wyman, a staffing firm. During the interview, she said, candidates should be asked behavioral questions that get them to describe how they demonstrated trust or teamwork or another core value.

Group interviews can be useful, Roccia said, so managers can ask about different values and the others can watch and evaluate. “You’re feeding off of each other. The co-worker is picking up on things that you may not,” she said. Then if there are concerns about a candidate, don’t ignore the warning signs but go back and ask follow-up questions.

Hay says she’s learned that she needs to listen to a wider array of Lanmark staffers, and make sure she values effective communications and an ability to work well with her team. She’s also paying more attention to cultural fit in hiring.

Her next COO — with the title vice president of operations — is likely to be an insider who’s worked at Lanmark for a while.

If so, he already knows about the bowling celebrations and chocolate chip cookie breaks, the need for speed and to pitch in on contract proposals — and the boss’s view that competition and fun and alpha women all come together at the office.

“If you really think about it, the people you work with really become your family,” Hay said.