I started to do this, but I made so much progress, the old photos lost there value to me...

I would take say 50 photos and only keep 1 or 2, I thought where ok but keep the bad ones in another folder

then again and again... only having maybe 6-7 photos out of thousands... + Movies

then you start noticing your hard drive nearly full... I got to the memory warnings, so you purge the rubbish and keep the few you like... then you also notice your doing better photos that make the first ones you had taken and saved look like crap... so you just keep the new ones again and discard the others and by now, your getting good photos out of just one or two new pics taken.

before you know it you have set yourself a decent bench mark to achieve... maybe then is when you compare you boy pics with your new girly ones... this is better content for motivation rather then keeping all the disasters to ponder over, by now you know what is working and what is not, so you just build on that.