Concept of provision for expense wrt conservatism principle

A provision for expense is setting aside a sum of money for a future expense that is certain to happen, although the extent of which might not be certain at the time. And when i say setting aside a sum of money, it does not mean that you actually take sum cash and put it in a locker, what we do is merely recognise an expense by passing a journal entry. For example it is certain that an entity would have to pay income tax at the end of an year, so a provision is made for the same at an expected amount by passing the following journal entry:-

     Profit & Loss A/C                                        Dr.                        XXXX

                      To Provision For Income Tax                                               XXXX

Now, the coservatism principle states that we should provide for expenses and losses as soon as possible even if there actual accurence is uncertain. On the other hand we should record incomes and profits only on there occurence. So, according to this view we make provisions for expenses well in advance.