Obviously, telling time is a super important skill for students to have.
Digital clocks, on the other hand, give the appearance of that time s a discrete event. When the digital clock says 2:43, that is all it says. With an analog clock, 2:43 simultaneously has the additional meaning that it is 17 minutes until 3.
I just wrote a 3rd Grade unit on time. To be honest, it wasn't until I had to writer this unit that I had given telling time much thought...let alone consider it an important skill for students to learn.
Read the unit here.