line weight

I see some comments about line weight- can someone explain to me what makes “good” line weight and what makes “bad” line weight?

Here is a good example of good line weight:

and this:

Bad line weight has a lack of dynamics and variation. It doesn’t help define the object.

Thick to thins, calligraphic lines to draw the viewer in. Vary the pressure and angle put on the drawing tool.

light to heavy, lighter construction lines, detail marks, and shading/hatching, heavier dominant features/forms, outside lines, lines that show depth (can you put your hand behind it?)

confident, smooth lines that draw through and extend outside of the form, lines that come from the shoulder and the elbow not the wrist or the finger

Bold outside, light inside is a good general rule. As mentioned by yo, lines that transition also add interest.

I’ve been trying to bold the lines on the shadow side and lighten the lines highlight side. The outside still remains bolder than the inside but it’s stroke weight is varied.

It really helps define the shape.

ok…I will try this technique on my current project (kitchen utensils haha) and see how it turns out.
Thanks guys!