I am not really sure what you mean by the term 'clean culture'........if you mean does the bark mulch somehow promote pests and diseases, the answer is no.

It depends on the source of the bark itself but some products will be extremely effective in deterring a variety of insects - red cedar, redwood and eucalyptus in particular - due to the higher levels of tannins and other essential oils these materials contain. Similarly, a number of these also contain antifungal/antimicrobial properties that prevent or limit decay.

Sometimes creatures like slugs, root weevils and pillbugs will shelter in wood chip or bark mulches but in nearly every case, the benefits provided by such a mulch far outweigh any possible negative effects.

I have never removed any mulch but could consider it only if the mulch were too thickly applied. Otherwise, any organic mulch will eventually decompose and add nutrients into the soil, some faster and better than others. And some, like compost, are recognized as disease suppressants.

I've been waiting for someone to post that woodchips and bark mulch harbors termites and carpenter ants. It's been my experience that they don't. If you do see them coming out of the mulch, invariably there is a buried stump or log that they are living in under the mulch.
I have never raked up my mulch and 'got rid of it'. Some people do, according to a garbage man I talked to once. He said they don't like the look of aged bark so they clean up all the old bark and replace it with 'better looking' new bark. Why they don't just add a cosmetic layer of new bark over the old, mystifies me. It would save a lot of work and money. That garbage man told me he picks up more bark on his rounds than I install as a landscaper!
Those people need to know how valuable decayed mulch is for the health of the soil and plants. I've never heard the term 'clean culture', but it appears it's not in tune with nature.
Mike