While older workers possess a wealth of experience that will enable them to mentor younger workers ("Age does not define one's worth, abilities" by Mr Jeffrey Law Lee Beng; Oct 13), there are also compelling reasons why many employers are reluctant to hire them.

Many senior employees find it difficult to function at optimal levels because their skills and abilities have not kept pace with the way business is done today.

They have not kept up with new work processes, technology and social networking, and may not interact well with younger colleagues.

This is not necessarily the fault of the older workers, since the skills of staff who have worked for the same organisation for decades may simply be outdated or out of step with what other employers require.

Though there are always exceptions to the rule, many older employees are generally less flexible and more difficult to train in new vocations; this is especially true for jobs requiring technical skills.

Many seniors are willing to take a substantial wage cut in a new job, but often end up less satisfied, productive and committed because they still yearn for that last drawn pay.

Older workers also have less energy, are slower and are more likely to have health problems than their younger colleagues.

Companies that provide health insurance will inevitably find older staff more expensive to insure.

While long-serving older workers are appealing because of their greater loyalty, many of them stay on simply because their skills are not in demand by other companies and age is against them.

Some members of senior management may prefer to promote less-capable staff rather than younger, talented individuals who they fear will outshine and, ultimately, replace them.

Hiring retirees or older workers may be an honourable notion, but many employers worry that they may not contribute to increased productivity or to cost savings.

Simon Owen Khoo Kim San