A registered trade mark does not expire provided renewal fees are paid every 10 years. However, if you stop using the trade mark as a trade mark it can be removed. Such non-use can occur in respect of some or all of the goods or services in respect of which the trade mark is registered. For removal, that non-use has to be for a continuous period of 3 years terminating on a date 1 month before the date of application for removal.
The mechanism for removal makes it relatively easy for the applicant for removal. All that is required is the lodgement of the necessary application and the official fee. The onus then falls on the owner of the registered trade mark to prove use within the relevant 3 year period.
In Shen v Gwei Ting International Fashion Corporation  FCA 1131, it was emphasised that even a single instance of use during the three period is sufficient. However, the use must be in "good faith". That phrase has a well understood meaning in this context in that the use must be real, as opposed to token, use in a commercial sense.