Done this once, though the band I left was well past its sell by date and split on my leaving.
It had started out in about 1999 as a covers band, I’d joined in 2001 on bass, and then morphed into doing glam/heavy rock originals. By 2008 and several line up changes it was stale, hardly gigging so when the opportunity of a position in a regularly gigging punk covers band came along I took it.
I told the first band, and with them all being mates (we were mates before we were bandmates) there were no problems, in fact it was almost a collective sigh of relief that there was a reason to finally stop.
The punk covers band had been together since 2004, lasted til 2013 and from that Knock Off, my last band formed, taking me on a musical journey I’d never have thought.
And to cap it all off, I’m now in a classic rock band with 3 of the guys who at various times were in the first band.