Help Consistent Internal Memory Issue

[newandroidnoob]

Ok, so i've been having this problem for I don't know how long. My internal memory will be fine one day( 40mb considering i've never been able to get passed that since I dont know when) then i'll install an app or 2 then it'll drastically go down to like 10mb and I dont understand why. I dont have nearly as much apps as everyone says they can have and that's one of the main purposes of me getting this phone was for the numerous apps I thought I would be able to install. I'm constantly having to delete apps without fully enjoying them yet because my stinking memory always declines. I can barely update my apps that I need to update because of insuffecient storage. I go in and transfer most apps to the SD card and clear some data from all apps that data can be taken from. Will I have to do a factory reset? If so what does that consist of, like what all will that delete? I'm always scared to delete data and the cache for some reason. I guess i'm just not understanding why my phone is always low in memory. Sorry for the long post but i just needed to address the issue fully. Also my phone is not rooted. Thanks in advance!