That sounds like a chapter in a who-dunnit, doesn't it? The Clue of the Part-pruned Hedge...
"Hmm," said Sheerluck Soames, to Dr Wotsit, the faithful sidekick.
"The gardener who is responsible for this bed is - let me see, five foot, five and three quarter inches tall, and has an aversion to using a ladder."
Every time I go past this section of hedge, I nip off any branches which are sticking out over the grass, so that whoever mows the grass can do so with ease, and so that the grass isn't deprived of light, which would make it die: and that would be really annoying, right by the gate, which obviously concentrates all the foot traffic.
And, selfishly, so that I can open the gate properly, get a wheelbarrow through properly, and generally just move around the area without having great big wet Yew branches thwacking me in the face.
Then, when I was weeding the bed, I was again being thwacked by over-long branches, and it was getting hard to reach some of the plants, so I just nipped back a few branches each time I was working there.
I hadn't noticed how much of it I had trimmed off - and oh look! What a lovely neat corner!