The state of carrying on your luggage when you fly is dismal. Fellow airline passengers are always antsy to get ahead in line, to board early before the overhead bins fill up. After all, no one wants to be the unlucky person stuck rearranging suitcases to fit their own.

Personally, I prefer checking my bag at the gate (for free!) — a last-minute move that releases me from the stress of searching for overhead space on a crowded flight. Most of my colleagues (and certainly other travelers) feel differently; they'd rather not risk parting with their possessions or spending extra time after arrival waiting for baggage claim.

No matter your preference, it's clear to anyone who's ever been on a plane that there's very little space available. Unless you're in first class or have early boarding privileges, there's always the added pressure to beat the crowd. It seems that airlines have finally found the no-brainer solution — adding more space.

In October, United was the latest airline to announce that it will install larger overhead bins on its main fleet by 2023. United's move follows similar upgrades from Alaska, American, and Delta, which recently incorporated larger compartments into their domestic flights.

As with many travel-related perks, there's a caveat: More overhead space doesn't necessarily mean you're ensured significantly more space for your things. Despite what airlines probably want you to believe, motivation to add compartment space isn't solely driven by improving customer experience. (If it was, then carriers' priority should definitely be to add more legroom and seat space.)

Adding more room for luggage increases boarding efficiency, since carriers lose money for every minute a plane doesn't leave on time. Airlines care about their bottom lines — a focus that has resulted in the industry standard of nickel-and-diming customers over different travel fees. Luggage space just happens to be the latest area in which airlines can optimize for more efficiency and, consequently, more money.

How carry-on culture got so chaotic

About a decade ago, before the era of inescapable travel fees, a plane ticket used to include at least one free piece of checked luggage. That changed in 2008, when American Airlines introduced a $15 fee for passengers' first checked bag, two weeks after other major carriers started charging $25 for checking a second bag. Bag fees soon became standard and have steadily increased over the years, with some airlines now demanding $25 to $30 for the first checked bag on a domestic flight. It only gets pricier from there: Second checked bags are about $40, while third bags are almost always $100.