The Age
Just like fine Wine, domains get more valuable with time! The older the internet gets the less meaningful, memorable, brandable domains are available for use, thus they yield higher value. Aged domains also tend to have higher backlinks and traffic than freshly registered domains.
The keyword/s
Domains which relate to certain industries have far higher value. If you look at the finance industry which is worth trillions, domains like finance.com money.com loans.com are worth minimum 7 figures. These names have high search volume and far greater brand equity than for example WeSellCheapLoans.com (no offence to whoever owns this name). One word English dictionary domain names sell typically for 5/7 figures. This year Hippo.com sold for $3.3m Floor.com $3.1m Marketing.com $2.5m meme.com $1.25m
Demand
The world is turning digital and digital real estate has never been in such high demand. Brands are literally buying up premium names left right and centre to secure their future in this digital world. As one word names become rare, 2 word names are increasing in value faster than a stolen Ferrari.
Sales this year: GoBet.com $850k LiveWire.com $632k ZeroCarbon.com $600k WorldClass.com $400k
The ROI
If you think spending for example $200k on a premium domain name is too expensive, but your company spends the same every year on janitorial products/tea/coffee and biscuits, would be wise to rethink your brand strategy. Domain names are balance sheet assets NOT P&L expense, they appreciate in value every year. The ROI over the life time of ownership completely outweighs the initial investment. Email security, brand protection, brand credibility, brand simplicity and trust, the ability to leverage the asset and pivot the brand; to some companies that's worth millions.
Your domain should always match your brand name, if it doesn't you DO NOT own your brand! Your marketing budget is increasing the brand equity of an asset you don't own!