Is this decision to be made by the owners or the management organisation?
You seem to not fully understand the management structure in strata schemes. Theoretically, the owners corporation (all owners) tells the strata committee what to do and the committee instructs the strata manager on getting it done.
In reality, the strata manager advises the strata committee on what they can and can’t do, the committee makes decisions on behalf of the owners corporation (if given the standard delegation to do so) but if a majority of owners don’t like the committee’s decisions, they can overturn them.
There are exceptions to this – such as decisions that the law says can only be made at a general meeting of strata owners – but that’s the way it works on most issues, in most schemes most of the time.