Shears that tear are usually the pivot
I spent a Sunday evening in late August on the front hedge, the usual late-summer cut. The first metre was clean. Then the blades started to ride. Leaves came off in strips. I thought they were blunt and I had a file in my pocket. The file was not the job. The pivot nut had walked half a turn. There was daylight between the blades. Every stroke after that was a chew. In the morning the cut line had browned, and I went back with secateurs to tidy wounds I had made.
Shears are for a face of growth. A hedge. A path edge. A lot of soft stems at one height. They are not a big pair of secateurs. Secateurs that stop cutting are usually blunt, and a stone often brings them back. Shears that tear are usually the pivot. The long blades only shear if they stay in one plane and meet along the length. A loose bolt lets them scissor past or gape. You feel it as a cut that starts, then folds the leaf and rips it.
I would not buy another pair until I have checked the old ones. Close the handles and look along the meeting faces. If you can see daylight, they will tear. Hold one handle still and wiggle the other. Play at the pivot is the fault. Tighten the nut until the blades meet and still open without a grind. If the nut will not hold a setting, the thread is worn and that pair is finished. A missing washer does the same job as a loose nut. The blades tilt. One rides over the other. I have put a washer back on and watched a dead pair start cutting again.
Sap is the other pivot failure. After a summer of privet or anything sticky, the joint packs and the handles stiffen. You force them. The blades twist off line. Wipe the joint. A drop of oil on the pivot is enough. That is the same winter habit I wrote about in Winter tools need a wipe and a film of oil. I would also do it after a long hedge session in August, not only in November.
The edges still matter. If the bevel is rounded and shiny once the blades meet, dress it with a file along the existing bevel only. I would not grind the flat faces. Grind those and you have built a gap that no nut will close. A nick from a hidden wire in the hedge will snag every pass. Stop. File it out if you can. If you cannot, that pair will chew the same spot on every stroke.
Skip shears with a rivet you cannot tighten. When that joint loosens you have a stick. Skip telescopic handles that flex when you squeeze. Length is not reach if the blades miss. Skip using shears as loppers on a woody stem you should cut with something that can span it. You will roll the edge and walk the nut. I would not take shears to a single rose stem either. That is a secateur cut, and I said so in September cut-back is a tool choice.
Skip the pair sold only by colour, or as never needing oil. Soft steel and a painted pivot still gum up. Skip the set that is shears, a toy saw, and a hedge bag in one wallet. You will use the shears. The rest sits until it rusts.
This shows in late summer. Hedges get their main cut once the birds are done, on a small UK plot usually August into early September. Path edges grow a fringe the same weeks. A torn hedge browns in the sun. A torn path edge looks like you attacked it. The same pair comes off the hook again when the jobs change for September cut-back is a tool choice, if you have a face of growth to take down at one height. A hoe that will not cut is usually the edge. Different tool, different fault.
I hang them closed, on a hook that will take the weight. A shed hook that actually holds a fork will hold shears if it is meant for a shaft, not a cup. I would not leave them in a wet heap with the pivot in the mud. The rust starts in the joint you need.
If I later add a buy link here, it will be a paid promo.