Oneworld is the best
 

Every possible airline rating organisation constantly has named OW the best

just recently skytrax

Why??

I would have thought star with a better coverage would be better

Look at the airlines in them.

At the very top level they're about equal (NH, OZ and SQ vs. CX, MH and QR) but further down the list Star has a handful of decent airlines but mostly they are average to poor.

OW has consistently good airlines throughout the range, and certainly no Egyptairs or Air Chinas who you would actively avoid.

In summary, quality over quantity.

I don't have a very high opinion of Skytrax, especially their airline ratings, but in this case I agree with them.

Star Alliance has a lot of carriers, but a lot are also-rans of poor quality. OW made a mistake admitting Air Berlin (without making them increase their quality) but overall all their members are airlines you might well choose to fly on. Star... not so much.

Star experience is not well unified. For example the number of per-airline exceptions on the Star RTW ticket is huge compared to the number on the OW RTW tickets. The infamous United Star-net blocking, limited LH reward availability unless you use Miles&More miles, etc, etc.

OW gives its top-level status members many of the perks of "First" travel (lounge [1], checkin, baggage priority, seat assignment, etc) and particularly top OW status is treated like top same-airline status on the operating carrier. Star gives top-level FF the "Business" experience.

So overall in my opinion OW gives a much more consistent experience across airlines in the experience, and a much higher-level experience overall. Since I, an d I suspect many other OW customers, travel very internationally on several carriers for business and leisure, this is important to me.

[1] Please don't rehash the BA Concorde Room, QR F lounge, etc... too much. OW Emerald still gets access to most alliance F lounges, *A Gold does not.

I was really impressed by my OW benefits when I traveled on AA. I know that AA system has some issues (in which they treat OWE like EXP), but my OW status actually saved me so much headache and pain.

Awwhh, come on, don't be so harsh on Air China! Air China is actually pretty decent! But I do agree that OW in general has better airlines. Furthermore, OW Emerald > *A Gold. I think that extra tier makes a real difference.

TBH though, I would quite like some small (maybe terrible) airlines to join OW so I can earn easy Sapphire/ Emerald (à la A3!). Mainly because OW's earn rates are ridiculously stingy all round - esp. for discount economy fliers.