What is interesting is that all religions started as a cult at some point.  When I see cult, I try to scrutinize the situation thoroughly and look for whether or not....

1) The cult follows the dangerous patterns as described here. 

2) If it is only called a cult just because it is not a recognized religion (some Neo-Pagan traditions are considered cults just because they are small groups not big enough to be a religion). 


Other than that, people should be careful when seeing the already noted.  Cults can exist anywhere, and for any religion.  People should always see 'why' the group is a cult.  Sometimes it is just because the group is not a widely recognized religion, but other times...there, well, is a reason why it is not considered an 'authentic/traditional/widely accepted' practice.  And then sometimes, these groups are not identified as a cult.

There are one or two of so-called 'Tantra' groups that would be classified as a cult because they exhibit behavior that shocks people, and behavior that would make authentic Tantrik practitioners vomit.  But then you also have groups called the Cult of Mary, which are not all a cult in the negative sense.


Sincerely,
ResplendentSeraphim