lol catch the bottom?
so you went back in time and caught the 2009 bottom of pennies
or
oh wait. that was the only true bottom..

what you are really saying is. when the price moves down, you buy..
so your saying you did not mortgage your house to buy in at one time but have put some in at one point and some more at another point and some more at another point when the price goes below a short term average (i rfer to as discount days)

you cant catch the bottom until its too late. as you only realise its the bottom after it has risen again, and risen for long enough to realise that it wont go back down again to define that past as the 'bottom' . meaning you missed it

the only way to play it safe is to not throw it all into one order and instead put funds into smaller allotments of funds and thus be in more control of buying/selling. instead of throwing and waiting