A/B testing is legal, all users have signed thecontract before using the services. However, when being asked if it’s ethical,it’s hard to say. From the users’ perspective, they definitely don’t want to bemanipulated by others without knowing it. However, if they are told that theiremotion might be affected during the experiment, they will all be cautiousabout it, which may lead to the invalidation of the test.
If A/B testing weren’t conducted, importantconclusions wouldn’t be made. It does no good to the development of companies.Furthermore, without more new findings concluded from tests, companies may notbe able to serve users better. This is a dead loop. Users should give moretolerance towards these test for mutual benefits.