Air travel may not be one of your priorities at the moment, but it's still a subject worth checking out when you're on break, so you can be informed and make the best travel-related choices to skip flying with certain airlines.

There are popular airlines around the world with high-quality meals, but not many people are aware of the popular airlines with large revenues. The latter is more important than the former because it's important to know how much an airline has earned in revenue, as of January 2020. These airlines may not provide top-notch customer service, but they did other things right.

So, without further ado, here's what the largest airlines in the world are worth, as well as why they're worth that amount.

10 China Eastern Airlines Climbed To $17.3 Billion

You won't find Americanized Chinese cuisine in China, but you'll find out that China Eastern Airlines earned $17.3 billion in revenue last year. The flight attendants are a huge chunk in the airline's success, as they're the perfect example of beauty and brains. The flight attendants are exposed to Chinese culture and language. Not only that, but the flight attendants are also well-versed in customer service and safety, which shows in their work in the friendly skies.

9 All Nippon Airways Slightly Leads With $18.6 Billion

All Nippon Airways (ANA) is another Asian airline with a mindset focused on hospitality. ANA's training program starts with receiving customers and gravitates to the cultivation of the mindset of omotenashi or Japanese hospitality. Hospitality is an important part of Japanese culture, as the Japanese welcome you with greetings and perks throughout the flight. That's the main reason why many customers are satisfied with their flights and decide to book another ANA flight next time.

8 China Southern Airlines Stands Tall At $21.7 Billion

On paper, China Southern Airlines may sound like just another Chinese airline company, but it's really not. China Southern Airlines recently unveiled its new lounge at the Beijing Daxing International Airport, and it's nothing short of amazing. China Southern Airlines now ranks in the Forbes World's Top 10 Biggest Public Airline Companies by Revenue, thanks to the size (of its planes) and profitability — and those annual earnings are expected to maintain a steady pace to increase by 2030.

7 Southwest Airlines Has An Exact Revenue Of $22 Billion

You might wonder: "How on Earth did Southwest Airlines earn $30 billion in revenue with its low fares?" Well, Southwest keeps their costs in check by buying the same airplanes — Boeing 737s, to be exact — to reduce the cost of maintaining and outfitting each airplane, as they all look alike. Southwest also motivated their employees to start cleaning a plane before the passengers get off for quick turnarounds to quickly fly again and earn more revenue.

6 IAG Holds Steady At $28.8 Billion

International Airlines Group (IAG) is an English-Spanish airline holding company for British Airways, Aer Lingus, Iberia, Vueling, and vice versa. Each year, IAG transports 97 million passengers to 255 locations on its fleet of 525 aircraft. IAG uses innovative technology to reduce carbon emissions. Also, IAG truly cares about their customers' flying-related concerns ranging from in-flight safety to climate change. That being said, it's a refreshing sight to see that IAG takes both corporate and social responsibility seriously.

Related: What Qatar Airways Offers That Other Airlines Don't

5 Air France-KLM Group Is A Dominant $31.3 Billion

Air France-KLM Group is a French-Dutch airline holding company for Air France, KLM, Air Cote d'Ivoire, Royal Air Maroc, and the like. The success of the Air France-KLM merger was based on factors like its annual cash flow, its in-flight spreads, and its li-fi technology. Plus its diversity among its employees unites passengers and staffers alike, as professionalism and expertise trump bias and stigma from the security checkpoint all the way to the boarding gate.

4 United Airlines Is On The Higher End Of The Spectrum With $41.9 Billion

United Airlines has laid the groundwork to become an excellent airline for employees, passengers, and investors. United's strategic initiatives reportedly generated $4.8 billion in revenue by January 2020.

United CEO Oscar Munoz said: "As we approach the new year, our operations are running well, our employees are more energized than ever, and we are ready to unlock United's full potential."

United can also thank the budget-friendly travelers for helping them meet their needs and add more options.

Related: 15 Airlines With The Most Attractive Pilots

3 Lufthansa Moved On Up With $42.3 Billion

Lufthansa is Europe's largest airline, and it has continued to thrive, despite being in the world's toughest airline market. As per Business Insider, Lufthansa has succeeded by taking advantage of the synergies of a large conglomerate, differentiating brands, and avoiding cannibalizing business. Moreover, Lufthansa has invested heavily in Eurowings in an attempt to make sure that it's far from a cookie-cutter airline and provides its customers with significant brand value along with a unique personality.

2 American Airlines Group Soared To $44.5 Billion

American Airlines is arguably one of the worst airlines in terms of customer service, but it has cut operations costs by incorporating the airline industry's first natural language Interactive Voice Response (IVR) system. The IVR system delivers fast self-service as well as a superior caller experience to American Airlines passengers. We'd also like to add that American Airlines is a forward-thinking company that takes good care of its employees, which translates into improved customer service.

Related: 15 Airlines With The Strictest Flying Rules

1 Delta Air Lines Holds The Candle At $44.9 Billion

Last year, Delta Air Lines earned a whopping $44.9 billion in revenue. Delta has always shown heart in its work, thanks to its values-driven culture. Delta is a people-oriented airline with top-notch customer service for its customers and a low attrition rate among its staffers. In addition, a Business Insider article reported that Delta turned its attention to its operational performance and showed that its passengers are willing to pay for reliability. Delta's an all-around good airline.

Next: Flight Attendants Know About These Safety Features On Airplanes, Passengers Should Too