In my youth, I was easily impressed by fine, detailed linework.
Fine lines are a great way for artists to show off. They also feel cool to draw. Artists such as Norman Lindsay (above) and Frank Frazetta (below) sometimes got so carried away drawing fine lines that they could no longer hear the muse urging, "turn back!"
As I matured, I noticed that the better artists exercised greater restraint and often employed heavier, bolder lines for emphasis. These stronger lines are like adding a lower note to the harmony.
Below, the great Alex Raymond draws an entire figure using a fine line, but comes back with a separate tool to make one bold stripe for that pants leg:
Here he does the same thing to accentuate a shoulder fold:
And here he uses that bold line to chisel the most wonderfully sculpted pair of overalls I've ever seen:
Once in a while there are very special artists who go even further. Working exclusively with a thick line they somehow manage to create sensitive drawings as descriptive as anything done by the fine line crowd. Here is the brilliant work of Noel Sickles:
When you draw with lots of fine lines, no single line is crucial; if you make a mistake, you can cover it up with cross hatching, or reinforce it with the lines on either side of it. But there is no place for Sickles to hide an imperfect line in these drawings.
Here is another superb example from Alex Toth:
Toth has captured a complex subject-- a group of people in ornate robes walking down a palace corridor under a trellis with palm trees outside-- and he has done so using a simple, bold line. Unlike the Lindsay or Frazetta drawings, this is a work of unimpeachable integrity and admirable restraint.
Finally, here is another powerful example of what can be accomplished at the thick end of the spectrum. The great Robert Fawcett was far too substantial to get distracted drawing button holes and strands of hair in this picture of tear gas at a civil rights riot:
Sometimes the less subtlety and precision in the drawing tool, the greater the subtlety and precision required from the mind and wrist of the artist.