Why did it get shovel pruned????

Theo

When I shovel pruned a couple of roses last season, I dug up one where I
used the native soil and one that had the soil replaced with a high
quality rose mix. The difference in root systems was remarkable - over
50%. The rose with replaced soil had grown and bloomed far better too.
It was hard for me to believe that I'd planted both as bare roots, at
the same time.