The attenuation of the yeast determines how much residual sugar (sweetness) is left in the brew.
For simplicity I'll use 1.050, or just us 50 as your OG. with an attenuation of 75% your anticipated FG should be 12.5. That's 50 divided by 4 = 12.5.
The lower the number is toward 1.000 (or 0 (zero)) the drier the brew will end up...the higher the sweeter.
The only problem there is you have to do the math so you know your brew is done fermenting and you don't bottle early just because it tastes good...it may not be done fermenting aresulting in bottle grenades in your future.
If your brew is within the attentuation range (64-72%, 68-75%, etc) then you're good.