Ah so not quite as you said, ummm and more as I expected.
When somebody is handed a suspended prison sentence it either comes without requirements or (more usually these days) with. They can include unpaid work, curfew orders or probation supervision. When the sentence is handed down they are told, quite definitively, that if they commit any further offences within the period of the suspension or if they fail to comply with the requirements the sentence will be activated. Judges and magistrates have guidance which suggests that unless there are compelling reasons not to do so or it would unjust in some way, the sentence should be activated in the event of a breach. This is reasonable as to do otherwise would defeat the object of suspended sentences. Even more than that, the probation service has a process which it goes through before "breach" proceedings are instigated and their clients are not routinely breached following their first failure.