I really don't think it's not about electrical engineering. I can't find any other suitable website to know scientific reasons for it.
You did not ask about general requirements or uses of voltage stabilizers. Your question was very clearly focused on one specific consumer product that you were considering: should I "buy this voltage stabilizer".
Any time a question asks about whether a specific item is "suitable" or "the best choice" then the question becomes a product recommendation.
Furthermore, questions about the use of consumer appliances are off topic. Your question was off-topic for both reasons.