A scary comment to hear from anyone, especially my clients.
Why? Because there has been no such thing as a verbal warning since 2009!
If staff are not doing what they ought to, then you need to have an informal chat with them. Remind them what they should be doing, e.g. coming to work on time. Find out if there are any reasons why that is not possible (!) and agree with them what is going to happen so that they can do what they are supposed to.
After you have “reminded” them 3 times, depending on the severity of the offence, then you can start the disciplinary process.
But you can’t give them ANY type of warning without following the disciplinary process. You shouldn’t go in with the idea of definitely giving them a warning either: that would be the in-house equivalent of “show trials”.
It always amazes me the number of employers who complain about the restrictions of the system to “tell employees off”. And yet when I recommend, in fact beg them, to start a disciplinary process to deal with a staff issue, they then say that they don’t want to “upset” the staff member, or come across heavy-handed! Madness! Employers don’t have a lot of tools at their disposal, but this in one of them, and should be used appropriately.
Giving a verbal warning (which means nothing legally) without following a process, could be used against you for a claim of constructive dismissal. Don’t do it!