Why one great company still feels safer than it is
Most of us know the big Australian banks. We bank with them, we see the branches, we've watched the share price for years. That familiarity is comforting — and our brains quietly translate comfort into low risk.
But a share price doesn't care how well you know the brand. A single company carries risks that diversification can remove almost for free: a bad lending cycle, a regulatory finding, a technology failure, or simply a decade where the market prefers other sectors.
Diversification is the only free lunch in investing — it can lower the bumpiness of the ride without you needing to pick winners.
Concentration risk in plain English
Concentration risk means having too much of your wealth riding on one outcome. Australian shares are roughly a small slice of the world's listed market value, and our market leans heavily on banks and resources. If you hold one bank only, you're taking a very narrow bet on a very narrow part of a very narrow market.
A diversified global model does something quietly powerful: it owns thousands of businesses across countries, currencies and industries, so no single failure can define your result.
~2%
Australia is only 2% of the global market. 98% of the world’s companies are outside our borders.
What this looks like side by side
| Single blue-chip share | Diversified global model | |
|---|---|---|
| Number of businesses | 1 | Thousands |
| Main risk | Company & sector specific | Broad market movements |
| Typical worst-case fall | Deeper and longer | Shallower and shorter |
| Recovery depends on | One company's decisions | The global economy over time |
| Income source | One dividend stream | Many dividend streams |
How we use this in practice
We're not anti-CBA, or anti any particular company. We simply size positions so that being wrong about one holding is survivable and being right about the long-term growth of global business is what drives your outcome.
If you already hold a large single-stock position — often from an employer plan, an inheritance or a long-held family holding — the conversation is usually about how to unwind it thoughtfully, with tax and timing in mind, rather than all at once.