Has anyone switched from client side to agency side successfully?

I am a marketing director at my first agency after working client side for over a decade. A very well respected agency consultant recently told our executive that 1% of client-side marketers that switch to agency “make it.” Most switch back. I have started looking for client side jobs in the last few weeks because the stress level is more than I signed up for - though I’m not sure if I’ve given the switch enough time. Are there long time client-siders out there who made it? What got you through the curve and what’s your story?