Merit (puṭṭa) is the quality of moral goodness and wholesomeness and is also sometimes called skill (kusala), virtue (sīla), beneficial (hita) or good (sādhu). In traditional Theravadin countries, particularly Thailand, the meaning of merit has been seriously misunderstood.
Today, rather than thinking of merit as a quality defining a particular type of behaviour, it has come to be thought of as an object or even a commodity that can be 'made,' 'accumulated,' stored up to be used later and even 'transferred' to others. This misunderstanding has had a corrupting influence on the practice of Dhamma in Thailand. All too often, people do not do good out of regard for the Buddha's teaching, for the simple joy of doing good or because it is the right thing to do, but in order to 'get' merit. For example, generosity (dāna) has been downgraded from an act of giving to a means of getting. Worse, people believe that they can 'make merit,' by performing certain rituals - putting gold leaf on statues, giving money to monks, circling stūpas, etc. - rather than by having integrity and being virtuous in their everyday lives. And all this despite the Buddha’s exhortation: ‘Do not think that an external action brings purity. The skilful say that purity cannot be gained by one who seeks it in outward things’ (S.I,169). According to the Padhāna Sutta, Māra, the Devil, tried to dissuade the Buddha from his spiritual practice by suggesting that he 'heap up merit' (cīyate puṭṭaṃ) instead, exactly the suggestion many monks make to lay people today. The Buddha firmly rejected this compromise saying: 'I have not the slightest use for merit' (Sn.428-31).
Misunderstandings and corruption creep into all human institutions from time to time and in this respects Buddhism is no different from other religions.