That was one of the key findings in recent Prospect survey of attitudes towards the National Trust’s performance development review system.

However, 60% of respondents believed that their manager had rated their performance fairly.

On whether PDR ratings should determine pay awards, 41% believed they should and 41% said they shouldn’t.

Almost six in ten respondents (58%) said that their PDR objectives did not motivate them to perform well.

A number of respondents pointed to a perception that higher ratings, most specifically the highest, were unobtainable due to the impact this would have on team wage bills.

Many respondents thought that line manager assessments were subjective. People had very different experiences depending on the length of service of their managers.

A common perception was that managers were under pressure to manage budgets or be seen to be challenging on PDR ratings.

There was also a perception that higher grades were more likely to receive higher ratings.

Prospect negotiator Matt Sperring said: “The survey results do not give us a mandate to challenge the principle of a link between pay and the PDR process.

“But they do indicate that Prospect should pursue a review of the process to ensure there is better consistency and fairness across the organisation.”

35% of Prospect’s members in the National Trust completed the survey.