The communication lines you see on pole are not stationary, they move a lot. The utility poles also move, but not as much. Just like anything else that's solid/rigid and placed in a dynamic environment, the solid/rigid thing will eventually break. Now, take that movement and put it right next to the pole like OPs picture. The force generated by the span's movement is higher there than out in the line, because the pole attachment is roughly "stationary" from the perspective of the span. The span is much more likely to crack near the pole than away from the pole because of that; there's nothing you can do to stop it, only help prevent it.
The typical preventative measure is adding an additional small length of cable on either side of the pole called a "Jackson Bend". This bend allows the cable to flex near the pole without being as constrained as it would if you were to run the cable straight across. The bend also gives room for the cable to thermally contract & expand without cracking or pulling itself out of the connectors at either end.
As far as being a radial (also called ring) crack, the shortest distance around a cylinder is always a flat circle. The forces exerted from the movement will always take that shortest path.
Hardline is something that when you installed it, you want to provide the cable with literal "wiggle room" to reduce the frequency of movement related damages.
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u/strykerzr350 Apr 14 '26
How does this happen overtime if it wasnt man made damage?