Hair growing different lengths

Okay so I know that a lot of people have different textures on their head. Like for me, the back of hair is naturally soft, curly and never tangles. The rest of my hair however, is the nappiest kinkiest knottiest thing ever. Before I started my journey, I had really short ear length hair but the back was like full neck length. Never BC'd or anything, just started working from there. Anyway, I do trim after each relaxer, but what I've noticed is that the back of my hair seems to grow faster than the rest. Like at one point my sides were just getting to full NL and the back of my head looked like it was trying for APL and it made a Deep V. Then I trimmed the back to shoulder length. Six months later I was beginning my journey and now another year and a half later (today) I was getting my hair touched up after a 6 month stretch. Most of my hair was hanging around collarbone length but that patch at the back...was grazing BSL! There was so much of a difference that I couldn't even pass it off as a V cut. It looked sorta like this ''_'' as opposed to V. I'm not sure if that's a good analogy. Anywho, my question is WTF??? Oh and does anybody else's hair grow faster in different places?

my hair grow in a "W" shape.  ive just learned to accept it and leave it alone.  

Aww man, I wish I knew that before I cut it. LOST SO MUCH LENGTH! Grrr. I keep trying to tell myself its just hair.

I think my right side breaks less than my left. I'll probably even it up when I blow it out I guess. Until then, shrunken styles that don't show the unevenness ftw!

hellz yes. the back half of my head outgrows the top half like mad. that part of my hair like as you described yours, never tangles, never knots. just soft easily managed curls. the top half? wild wild west, and it lags behind in retention and in my opinion growth too. it's weird. if i didn't go out of my way to keep the back half the same length roughly as the top, my hair would easily have been down my back now. the pressing pictures i took in the pressing forum most of that long length you saw there was the back half. the top half only reached my neck, but you couldn't tell because the back of my head is just so thick and solid all unto itself! it's crazy!