Actually, no, please, don’t lie.
But if you’re looking to make a move, rather have:
Anything, that shines a positive light on you for looking elsewhere.
Yes, the job market is hot.
Yes, you want to see what’s out there.
Yes, your past colleague who just left received a huge salary bump going somewhere else.
And while those types of answers might be valid reasons, I don’t know how well they’ll hold up when asked by a future employer on why you’re looking.
Especially, if you’ve only been with your current employer for a short period of time.
As a recruiter, employers often ask me why.
They don’t want to run into the same situation.
I’m on your side to help, but thought I’d point this out, as we’re hearing this quite often in today’s job market.
On another note…
How about some Jonny Lang lyrics (one of the greatest guitar players out there, IMO).
“Lie to me
Oh, and I’ll just try to make believe
That everything, everything you’re tellin’ me is true”
~Lie to Me (1997)