I move banks from time to time for various reasons. I've never regretted switching. Same thing with internet providers and electricity providers.

In fact I was with Nova Energy and they wanted to raise my rates by something like 35%. Not only did I avoid that 35% raise but I actually got another 10% below what I was already paying by switching to Mercury. Companies will absolutely take advantage of customer inertia and mistreat you presuming you won't bother switching.