Of course salaries are a crucial issue. There has been a larger than ever percentage increase in salaries this year. The Silicon Valley firms set the ball in motion earlier in the year when they hiked up salaries and it has not stopped rolling since. The Magic Circle firms responded aggressively while the response so far by the medium sized firms has been varied. Some have set out to directly compete with the global firms while others have made it clear that in the long term, paying these salaries is simply unsustainable for them.
Salaries are of course a high motivator.
But it is not the only motivator. If it were, then the US law firms would be meeting all their ambitious recruitment targets.