Self managing might sound like fun but it can turn out very badly if you don't know what you're doing. Having an SMSF requires a lot of work. Some of the worst losses in super are through SMSFs which begin with small account balances (by that I mean less than about $200k) because the fixed costs involved to keep them afloat are quite high. It's normal for a fund to incur upwards of $2,000 a year administration fees) plus as trustee of the fund you report to the ATO directly (i.e. you have to pay the tax on your investments to them).
People want to get into SMSFs so they can access unconventional investments that they otherwise couldn't, but some of those investment ideas end up being total unmitigated disasters. In particular, the biggest losses come from one-off 'big ticket' buy decisions involving committing all of your superannuation capital in one investment and either taking out debt, or lending your money to someone else. Buying property off the plan at inflated prices or getting into some kind of seemingly cool unlisted development trust are two of the best ways to see your equity evaporate or your capital never returned.
On the other hand, with a fund that is regulated by APRA, whether it's a retail platform or an industry fund, as long as the costs are pretty reasonable, you're going to have a bad year here and there (the financial year ending June 2022 is a case in point) but it's very likely that you'll get 4 out of every 5 years at least of positive investment returns which over time, and by using dollar cost averaging, (contributions regularly going in when the market goes down as well as up) you're buying investments at a discount when the market is down, and will be served well in the long term. There are many industry funds out there which provide excellent investment choice, low fees, and cost-effective insurance options.
