HR expert says you’ll be fired for thing ’employers can’t come back from’

An HR specialist has lifted the lid on the workplace blunders that could cost you your job. Many people assume that dismissal stems from a single dramatic incident.

However, according to HR expert Kate Underwood, the reality is that it typically results from a gradual accumulation of smaller behaviours that eventually erode an employer’s trust and patience. Contrary to popular belief, it rarely comes down to minor office irritations or the odd innocent mistake.

Kate Underwood, founder of Southampton-based Kate Underwood HR and Training, said most employers could cope with staff occasionally getting things wrong. What raises serious alarm bells is poor judgement, dishonesty, or persistently overstepping professional boundaries.

She said: “Most people don’t lose their jobs over one tiny mistake. It’s usually a slow build-up of poor judgement, ignored feedback, attitude problems, or repeatedly thinking the rules are for ‘other people’.”

One of the most significant warning signs for employers, Kate noted, was dishonesty.

She added: “Honestly, most employers can deal with mistakes. What they struggle to come back from is lying. Once trust has gone, it becomes very difficult to rebuild.”

She also cautioned employees against firing off heated or confrontational messages in moments of frustration, particularly via email or internal messaging platforms.

She added: “If your message starts with ‘With all due respect…’, there’s a strong chance respect has already left the building.” Another escalating concern for employers is staff regarding workplace policies as suggestions rather than requirements.

Kate said: “Policies around social media, confidentiality, harassment and data protection are not inspirational suggestions. They exist for a reason and employers take breaches very seriously.”

Publishing content about work online continues to be among the most frequent ways employees find themselves in difficulty, especially when grievances emerge on social media platforms.

She said: “If you are ranting about your boss online while your colleagues are literally tagged in the pub photo beside you, that is usually not going to end well.”

Kate also cautioned that conduct dismissed as “banter” can rapidly develop into disciplinary matters if it overstepped professional boundaries.

She added: “The phrase ‘it was just a joke’ is often where things start going downhill very quickly.”

Attendance and communication represent another significant source of workplace friction. While employers acknowledge that life can be unpredictable, repeatedly vanishing without explanation or consistently turning up late without communicating can severely harm professional relationships.

Kate said: “Life happens. Trains fail. Children lick walls. Chaos exists. But disappearing into the abyss without telling anyone will frustrate people very quickly.”

She added that staff often underestimate how gravely employers regard matters surrounding the falsification of records, expenses or sickness absence.

She continued: “Nothing says ‘career-limiting decision’ quite like fake timesheets, mileage claims or compliance logs. Working another job while off sick is another huge issue, especially if somebody has said they are too unwell to work but is then posting online from somewhere else entirely.”

Crucially, Kate emphasised that strong performance is no justification for poor conduct.

She added: “I’ve seen genuinely talented people walk themselves straight out the door because they believed being brilliant at their job gave them immunity from behaving badly. Being excellent at your role does not cancel out poor conduct.”

As workplaces continue to evolve and the boundaries between professional and personal life become increasingly blurred, Kate warned that employees must bear in mind that their behaviour — both in and out of the workplace — can still carry serious repercussions.

She continued: “People often think probation periods or informal workplace cultures mean the rules do not fully apply yet. But employers are always paying attention.”