Sheryl Sandberg of Facebook spoke to the BBC... "Facebook's future - ads and Android"
We made a pretty big bet on HTML5, hoping we could build our applications once and it would work on all the different operating systems
I wouldn't read too much into her choice of words here if it wasn't a common refrain and a completely misguided one. Facebook was hoping they could use HTML5 to achieve their goals across platforms.
Devout HTML5 advocates often argue that current development should be done using HTML5 based on capabilities that it might have in the next several years. Facebook must have overestimated the capabilities of its engineers, which are undoubtedly top tier talent. Somehow they must have thought they could overcome the limitations of the platform at the time.
I find this confounding - one of the primary reasons for using HTML5 is the "write once, run anywhere" mantra, but Facebook is not hurting for engineering talent, the ability to attract talent, or the money to engineer solutions using the best possible solution for any number of platforms. Why choose to limit themselves from the outset on mobile? (Yes, I already answered my question -- engineering hubris).