most comments so far seem to be about payment mechanisms, whereas the question was about membership.
In most territorial societies most members are affiliated to a tower, with only a few members 'unattached'. By 'direct membership' I would assume members were not tower affiliated but just 'members'.
That woild also probably mean members were not be affiliated to a branch either, since the branches are defined by the towers within them. So if branches are still needed some other means would be needed to fund their activities. One might be tempted to 'do away with branches', but in the societies I've been involved with, the branch is the unit that runs most activities for members, and the one that members associate with rather than the more remote central society. (I realise that might be different in smaller societies.)
Direct membership would also require a central payment mechanism (which others have commented on) but the reverse isn't true - it's quite possible to implement a central payment mechanism with tower/branch based membership. We are currently running a trial to do just that.
What other effects would direct membership have?
It may well strengthen the link between members and the society for those who remain, but if membership becomes just a personal choice then I suspect far fewer would join than do in the current regime, where all members of a tower are encouraged to join. You might argue that societies would be better with a much smaller, but more committed and active membership than they are with a much larger membership diluted by inactive ringers who hardly ever participate in society activity - but it would be very different.
With no link between members and towers the idea of a territorial society would be weakened, so societies could develop fuzzy borders based not on carving up the territory but merely on how near the activity ringers need to live to be interested. And without a well defined patch of land to define them, some societies might fade away while the more proactive ones expand.
How much of the above would be good or bad can be debated - probably some of each - but it would be quite a different landscape
Going one notch up the ringing structure, the question of 'direct membership' is mor usually discussed in relation to the Central Council. Post reform, it's constitution requires it every few years to consider whether the ringing community would be better served if ringers were direct members rather than being indirectly represented by the ringing societies. That would be a significant change, with potentially significant benefits.
At the first review the Execitive concluded there wasn't support for it yet. But i suspect if we already had it then most people would see it as normal. It's the change that seems impossible.
We've been here before. Twenty years ago I dropped the proposal for an Instructors Guild because although a lot of people wanted it a lot of others were strongly against, and too few supported it. At the time I said it would seem quite normal if we already had it and I predicted that in ten years something like it would arise bottom up. The timing wasn't far wrong, we now have ART.
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