Did the Eccentrics help?

I had an errant tick that drove me . I used a mechanic stethoscope to narrow it down to which valve it was but I still couldn't find WHAT was doing the ticking... until the rocker arm broke. There was a tiny crack that I couldn't see on the underside - it would be quiet for the first few miles after I adjusted it, then go noisy again, until one day it just broke.