Why not? it even has a name it's called DCA (dollar cost averaging)
Discussion
No it’s more of a periodic lump sum buy where he’s immediately converting all available cash on hand as soon as he gets it. DCA means you have the funds on hand and you spread out the purchases in fixed amounts over a set period of time. With DCA, if the price dips, then you actually would have some cash on hand to buy more if you wanted to. If you lump sum every paycheck, then you don’t. Both are good strategies.