Just to add a little to your points, I was a consultant working...

Just to add a little to your points, I was a consultant working for a small Victorian company that had built a software package for Local Councils. This was back in the eighties and we had about 70 of the eighty odd councils that had gone to tender at that stage. At a couple of Local Council conventions towards the end of the eighties I noticed a small Queensland private company that presented a very "state of the art" product and I'm pretty sure that this company morphed in some way into TNE.

You're correct about the software requirements of Local Councils (unless it's changed a lot since I was familiar with it),
The general financial accounting software requirements are quite bland. There's no call for costing data as in manufacturing, none of the engineering add-ons required by miners and distribution and perpetual inventory records were unnecessary.

This means that there's probably not too many great opportunities to move outside the world they have built their success around without some development.

The power computers that came in the nineties when linked with smarter use of database techniques gave rise to the parameter driven software which in turn provided software companies with the chance to provide packaged enterprise solutions i.e. one product to meet the needs of an organisation.

This was the start for SAP, Oracle and many others (not all of whom made it through to the other side). TNE was a provider of such an enterprise solution but concentrated on Local Government only.

For TNE, this meant a need to build modules around the Council's rating requirements and reports, together with code that recognized support services that were partially subsidized by State Governments, which is, I think, the patient management stuff you referred to. They were, in those days anyway, the only variations required to meet Council requirements.

The thing was that these software suites could be easily introduced into "greenfield" sites that existed at the time. Most councils, or other organisations in the case of SAP and Oracle, had no IT support of any consequence so it was easy to slide new sophisticated software into place.

As you suggested, these days, most organizations of size have already implemented an enterprise solution. To replace a domiciled solution with TNE (or SAP etc) capturing all the history along the way, when the incumbent software and database is not fully understood, is not for the feint hearted and it's why most software houses talk about sticky customers. It's not because they love their current provider, but because a change is, in simple terms, a hard thing to achieve and, certainly, very risky.

I would think therefore, that there's very little chance of TNE losing customers but finding new ones is difficult.
Councils sometimes split as they become too large so there's an opportunity there but that's not a frequent occurrence.
New legislation was/is another way of increasing annual fees.

I've never owned TNE and only glimpsed at their financials so can hardly hold a view of their worth as an investment but I'm pretty sure that the path they travel down across the next twenty years will be different to the path they've been travelling down, albeit that I'm sure they're capable of continuing success.