DCA is effectively scam pushed by brokerage firms to pay more commissions (for stocks, N/A to bitcoins). EVERY TIME they will defend their position by giving the example where you start buying at Price A, then price moves down to Price A/2, you accumulate 2x as much stock, then the stock takes off and you have more stock. What if the volatility is to the upside, and not the downside?
Take this example:
A)
You buy $5,000 bitcoins at $8 (625 coins)
-or-
B)
You buy $1,000 bitcons at $8 (125 coins)
You buy $1,000 bitcoins at $10 (100 coins)
You buy $1,000 bitcoins at $15 (66.67 coins)
You buy $1,000 bitcoins at $25 (40 coins)
You buy your last $1,000 bitcoins at $50 (20 bitcoins)
Would you rather have $31,250 worth of coins in scenario A, or ~$17,500 in scenario B)?
If you believe in an asset, invest what you are willing to lose when you have the funds. Turning $31k trades into $17k trades is for losers.
Dont get me wrong, if you are working with an income stream - putting int $1,000 per month - then you will be DCA by default, but its not a 'strategy' that is +ev. I would argue if coins are going to $1000/btc, you are better off buying now no matter what the volatility may bring.
Well, sure. If you're confident that an asset's value is going straight up, with zero fluctuation, congratulations; you don't
need any advice. Buy, buy, buy, because this price will never come again.
But most people aren't Brainiac. Most people don't
know that an asset's price is going straight up, with zero fluctuation. Heck, I've never
heard of such an asset, even in hindsight. Generally, even if an asset is going up, there's fluctuations within that uptrend.
So, in the straight shot up that you propose here, we've established that the time to buy is "right away". But zoom in on (e.g.) the Bitcoin market, and oh, the roller-coaster ride we're having! It's been fluctuating between $8 and $9 for almost a week now! If someone wanted to buy in a few days ago, and bought at $8, they'd win against the guy who bought at $8 and $9 and $8.50 and $8 again. But the guy who showed up during the first big push on Monday night/Tuesday mornihng would have bought at $9 and done
worse than the averaging guy.
Admittedly, there's an advantage to the brokerage for them to recommend this strategy when they get paid by the trade. But there's also a practical use for it, when per-trade fees are removed: once you get to a granularity where you don't know how the asset is moving anymore, how do you minimize the risk from that turbulence when taking advantage of a bigger-picture trend? Cost averaging says: don't put all your eggs in one moment's basket. Spread out, and you can act on the scale at which you're thinking.
Edit: All that said, I think a year is too big an interval for buying in to Bitcoin, if you're intending to do any speculation with it.