Question: What are Buddhist meditative practices for? Can they be for relaxation and the sharpening of mindfulness for work and play?
Answer: They are for training, to attain enlightenment, which leads to liberation from the cycle of birth and death. If this original purpose as above is forgotten, with meditative practices learnt and done only for worldly and thus limited benefits, with no further noble motivation, that practised cannot be considered authentic Buddhist meditative practices, as taught by the Buddha.
The Buddha never intended anyone to practise what he taught without the basis of ethics or without eventual advancement towards liberation. If done this way, without right foundation and goal in mind, so-called relaxation and mindfulness gained might even further attachment to the worldly, without any moral guidance too, which will only further trap one in rebirth.
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https://thedailyenlightenment.com/2016/08/what-are-you-practising-mindfulness-for
Mindfulness Of Buddha Is Supreme Meditation
https://purelanders.com/2012/01/16/buddha-mindfulness-is-supreme-meditation