Keyboard vs. Mouse
The mouse serves newbies. High octane "professional" users tend to prefer the keyboard for speed.
"Texting" on handheld devices is the new skill
Historical Anecdote In '95 we were migrating a "green screen" command line-driven online equity trading system (one of the first: Instinet) from keyboard-only entry to this newfangled, glitzy, mouse-driven, graphical Windows interface.
One of the major challenges - and a design mandate - was to include the keyboard shortcuts along with the gooey/mousey UI.
And with good reason...
Experienced traders could execute a trade task in no time flat - in an environment that values speed and is very keyboard friendly. They already knew the keystroke shortcuts and the trading Ticker symbols by heart. They didn't want to be slowed by mousing around or learning a whole new interaction mode.
Furthermore, the veteran "power user" traders were already generating money hand over fist (... and very quickly, thank you)
Many of us easily use "universal" keyboard shortcuts for simple repetitive tasks that share a common keyboard convention (like Delete, Cut and Paste).
Have you ever tried to fill out an online form that DOESN'T conform to keyboard tab-order conventions?
In simplest terms:
Browsey page-wandering lends itself to the mouse.
Doing repetitive, complex stuff (especially text-heavy content entry & management) can be improved tremendously by effective keyboard shortcut tools.
UI Design is often Seduced by the Rodent.