'worsen performance' is correct and usable in written English.
You can use it to describe a decline in the quality of a process or action, or to describe a decline in the quality of the results of a process or action. For example, "The lack of adequate resources has caused the company's performance to worsen."
The union argues that proposed workforce reductions at Verizon will worsen performance.
On the other hand, for energy harvesters with a bi-stable quartic potential function, asymmetries in the restoring force appear to worsen performance especially for low to moderate noise intensities.
Studies have shown that monetary rewards can undermine motivation and worsen performance on cognitively complex and intrinsically rewarding work, suggesting that pay-for-performance may backfire.
If the original decoding introduced an error, then the iterative process may worsen performance as the motion-compensated interpolation (MCI) process may produce worse quality SI.
Although high anxiety may worsen performance and increase the risk of injury, its impact is quite variable among athletes, even among those with similar skills competing in the same event [ 23, 24].
The worsening performance of the loans has squelched demand for mortgage-backed securities.
Another possibility, said an executive involved in structuring the deal, is that the price of the Manville acquisition is renegotiated altogether, given the company's worsening performance.
Some economists say Germany's worsening performance -- its economy slipped into reverse in the third quarter, the latest statistics show -- could drag most of Europe into negative territory.
Two years ago, the then chief David Brennan was forced to quit after a row over his £9m pay deal and a long period of worsening performance at Britain's second-biggest pharmaceuticals firm.
His predecessor, Danny Breithaupt, had blamed increased competition for Frankie and Benny's worsening performance, but the new chair, Debbie Hewitt, who took over from Alan Jackson in March, admitted it was not the main factor.
Gearing up for a Christmas flop, the chocolatier blamed "high levels of promotional activity in the marketplace" for its worsening performance during the festive period, normally its biggest selling season of the year.
