ASB dividends usually hover around 5–6%, while the loan interest can be higher, meaning you could end up paying more than you earn.
On top of that, inflation can eat into your returns, so the real gain is even lower or negative. If inflation is, say, 3–4% per year, the real return on your investment after paying loan interest is negative
dividends can fluctuate. If the payout drops, your effective loss increases.
So financially, it often doesn’t make sense to take an ASB loan.
In short: paying cash is safer, and your money grows steadily without the risk of losing more than you gain.