EDIT : I was thinking that that maybe I get wrong results for the SkewedLeft15 graph(I talked about above) because it isn't a Left skewed graph in the first place. And so, I stumbled upon the skewness calculator which tells you what kind of skew(Left/Right) your graph is.
But now I'm even more confused because even for my first graph(data : 1,2,3,4,5,2,1 which is clearly Left skew in my opinion since most values are coming before the mode which is 5), the skewness calculator gives a positive value of 0.4429 which indicates it is a Right skewed graph. How's this possible ?
You may check Skewness Calculator, Definition, Formula & Calculation to calculate skewness.