Sometimes the nature of the job changes, because of new technology. Good employers will ensure that employees are given adequate training to cope with the change in work.
Sometimes employees find they are no longer capable of doing the work for which they were taken on. If there is no alternative (i.e. no possibility to reduce your hours or switch to an alternative role) an employer may ultimately be entitled to terminate your employment.
However, where the reason for not carrying out some duties is related to an individual’s disability, he or she will be able to claim additional protections under the disability discrimination provisions of the Equality Act 2010.
Where your employment was terminated because you could not do essential parts of your job, this may be a lawful dismissal on account of capability. However, your employer would still need to show that it was fair to dismiss you on those grounds.
Therefore, before contemplating dismissal, your employer would need to consider what steps could be taken to help you do your job properly, for example giving you adequate training. Employers are also obliged to follow an appropriate disciplinary procedure prior to dismissing an employee on capability grounds, or risk losing an Employment Tribunal claim.