A balanced fund hides volatility from you, so that can be an advantage for folks who do not like to see big drops (nobody complains about big gains) in their fund.
But when you withdraw from a balanced fund, you are selling equities AND fixed income, when it may have been better to sell one or the other.
Balanced fund in taxable is less tax efficient. This was discussed recently at length on the forum.
If you have a tax-advantaged account and cannot force yourself to rebalance (buy low, sell high), then let a balanced fund do it for you.
It's all about short-term opportunistic rebalancing due to a short-term change in one's asset allocation, uh, I mean opportunistic rebalancing, uh I mean rebalancing, uh I mean market timing.