Sketching is quite a fun thing to do when there's ample time but those dark moments are always there when distractions an frustration comes in; especially when the resemblance to the real picture isn't forthcoming.
I started out the sketch above three days ago and I'm still stuck with it. When I think of the long hours I'll spend shading the hair of the lady, I feel discouraged.
Sometimes, it takes my genuine interest in a picture and motivation to be able to complete the portrait sketch.
In my case, I use ball point pen with no chance of erasing when there's a mistake. So, I'm extra careful. I hope to continue and complete this sketch today :)