In our complex of townhouses it would be impossible to know if an owner has changed something without permission. Unless someone questioned every ute that was seen in the vicinity. So someone here could have changed the aluminium sliding doors with wood french doors – and we would have no idea! Does the EC/OC have to insist on inspections of properties to ensure nothing has been changed? Do they have to put in cameras to see if tradesmen go into a unit or if building materials are delivered? Should the OC inspect a property when it is put on the market so the new owner doesn't ask for a repair on something that shouldn't have been there?
I worked in a large company where if you changed jobs (say from paper sorter to paper filer) you had to sign a contract which stated what the company expected of you, what you had to abide by (OHS etc) and what you could and couldn't do. In that way, even if you ignored what was stated in the contract, the company could not be held liable if you did anything they warned you not to in case of injury. It also gave them cause to take matters further in other matters (ie the don't come Monday talk).
Perhaps that is what is needed for strata. When someone buys or moves into a strata complex they have to sign that they know it is strata, that they can't do this or that without permission and spell out what they can do. Why should other owners pay for expensive changes that were not approved? Or pay for repairs when unauthorised changes cause damage to common property?
Will this stop people from changing things in their unit? No, I don't think so. But it could perhaps limit the liabiliy of the OC/EC. If an owner/resident signs that they know they are in strata and know its rules, then they should be held accountable for their actions, not others.