Travel may broaden the mind, but Bartlett's globetrotting career has also fine-tuned his people skills.
"I think it makes you very tolerant and culturally sensitive," he says.
Bartlett says he can often see misunderstandings before they happen, when colleagues make errors or assume the wrong thing.
In New Zealand, Bayer has 27 nationalities working across its divisions.
The company's operations range from marketing its consumer healthcare and pharmaceutical products - including its flagship Aspirin-based pain relief - and animal healthcare, to a manufacturing and research facility - a legacy of Bayer's $138.5 million purchase of local animal health business Bomac in 2011.
Bartlett says it's easy to have eight or nine countries represented around the meeting table.
"You hear it and you see it going wrong in the misunderstandings, in the way some people deal really direct and in straight lines whereas other cultures might approach it more softly."
He can see people get up to leave a room and know intuitively that not everyone is thinking along the same lines.
The diversity helps bring different ideas and perspectives to the table, he says, with different cultures stepping up differently during company-organised events and team building. "I just think it makes it exciting."
Every now and then he gets a missive out of Bayer HQ with diversity goals attached.
"I keep saying to them: we can't do anything more for diversity down here, we are so diverse."
You hear it and you see it going wrong in the misunderstandings, in the way some people deal really direct and in straight lines whereas other cultures might approach it more softly.
Selling drench for cattle and flea treatment for cats wasn't Bartlett's first career choice - his original plan was to be handing out the medication as a vet.
But after several attempts at getting into vet school in South Africa, Bartlett was set to continue his postgraduate study in parasitology until a call from Bayer set him on a different path.
His then-girlfriend, tired of his extended period of university study, had applied for a job at Bayer's local research station on his behalf.
He went on to marry the girlfriend, and his three decades with the company kicked off by researching products for malaria control, rat poison and horse fly control.
Very quickly, his natural ability to chat with customers saw him pulled into the marketing side of the business.
With ambitions to take his career further, Bartlett headed to the German head office in the early 1990s, which meant spending the first three months intensively studying German in order to get the fluency required to manage day-to-day.
Twenty years on, he says he can still understand German TV and read the German papers.
"It's still there but it takes my brain a little bit of time to switch in."
I keep saying to them: we can't do anything more for diversity down here, we are so diverse.
He returned to South Africa for a decade in a variety of roles, including a project testing the efficacy of pyrethrum-impregnated mosquito nets for malaria control.
The result of those large scale tests is that 40 million nets have now been distributed by various companies and aid agencies in Africa.
Ten years ago, Bartlett decided he needed a fresh challenge.
The company's offer was to run its Vietnam operation for three years.
"I'd never even been to Asia," he says. It was a massive culture shock - his youngest daughter, then aged seven, burst into tears on the second day, asking "Daddy, why did you bring us here?"
But Bartlett quickly knew it was a great move. "I think just because it was so different and so exciting.
"Every day, either privately or in business, there was something happening."
Even his daughters now say it was the place they loved living the most.
In Vietnam, the task was to turn around a struggling local business, which meant ditching the existing strategy in favour of a focus on products for the booming aquaculture market.
"For me it was a defining moment, to say: you can do this."
After previously working as a marketing manager or a project manager, the country manager role was a leap into leadership - something he loved.
The three-year stint stretched to five before the career itch set in and he shifted back to Europe to head the animal health division in the Benelux countries, before returning Down Under in a similar role at the newly expanded New Zealand business.
Over the years he's had offers from other companies, but says the shiny remuneration packages haven't stacked up against the fair treatment and opportunities he's received from Bayer.
New Zealand is home for the next two years until Bartlett will need to make a decision about localising or doing another stint overseas.
But with his daughters studying at New Zealand universities and a boat parked in his garage, it looks like he might finally be able to retire that box of electrical plugs.
