On my last visit, I have never seen so many kids so captivated by the parrot in Mutiny Bay. It's such a great effect -
UK parks used to be full of great passing features like this and the only reason we still have the Mutiny parrot is because it was recycled from Pirates 4D at the right moment that attraction closed. Merlin would never ever build them new like this now.
The moment they need servicing (like any effect ever, digital or mechanical), Merlin parks will 8 times out of 10 not notice until the fault has got too bad to be fixed easily, or when it comes to needing to spend on big repairs (since regular
maintenance never happens) simply say 'No, it's a small nice-to-have, nobody cares anyway', meaning the effect disappears completely.
Rarely do any of the people making those budget decisions actually visit from the guests' point of view and see what a difference effects make, or see it from a hands on point of view.
Includng fine details like lighting, audio, smoke, smells, which public won't individually notice but are the basic bread and butter of creating a good themed experience. Let those decline and your ride will decline, and the public will leave with a much lesser impression. Bear in mind theme parks rely on repeat visitors, who will notice more in a ride the more times they visit.
Parkwide maintenance of this kind of thing in Merlin parks usually falls to tech services and not a dedicated team. Tech services, it has been proven in many parks many times, are far too busy with the daily engineering duties and H&S side of things to have any time, effort or budget left for the frilly bits on the side that make up the guest experience.
Tech services in theory have the knowledge and capability to maintain these things, and often take ownership over them, but don't (it has to be said) have the specialist attention and experience to keep things as best as they should be. They are often very pressured in other responsibilities too.
But this is a problem that goes back a long time before Merlin – Tussauds parks never had professional/ dedicated teams for FX maintenance either.
The big difference between then and now, however, was that effects were usually far better value-engineered (money invested in backstage quality & reliability) than today. Surprisingly often, newer rides have poor quality effects or systems that havn't been designed for easy servicing. This is usually due to the dysfunctional scale of Merlin and the disconnect between Merlin Studios and the parks (and their separated budgets).
And even then, does the problem lie with Merlin for investing too little in the value of their rides, or the manufacturers for poor build, or both? It
all depends case by case but I agree it is currently a problem in UK parks much to the detriment of the guest experience.
Worth considering also that effects/ backstage systems tend to be a lot more complicated now than they used to be, but at the same time they have changed to become more self-reliant and automated. So it's a few steps forwards and a few back.
I agree with
@Rick that there's the odd case where a completely external factor (like hosepipe ban, or the environmental order) means an effect has to be made redundant. Still, it shouldn't be used as an excuse for the park to say 'well we've done alright without it this year, let's not bother spending any money to bring it back next season'. It all adds up for the guest.