Mt. Everest may be the tallest mountain to climb, but it's not the most difficult. Factors like technique and commercialization contribute, according to 3 professional mountaineers.

Hundreds of people stand atop Mt. Everest each year. But far fewer summit the Seven Second Summits, the second-highest peaks on each continent that push climbers to their limits.

Daniel Prudek/Business Insider

• When climbing huge mountains, height and difficulty don't always go hand in hand, mountaineers say.
• Mt. Everest may be the world's tallest peak, but it's easier to summit than other smaller mountains, like the Seven Second Summits.
• Three professional mountaineers...