Nowadays, we can see  of a lot of new paid to click sites (PTCs) on the internet almost every other day.  But quite unfortunately, most of them turn scam sites over a period of time. There are only a few exceptions to this.  In my personal view, it is not possible to make a decent income from PTC sites in a short period.  To earn a decent amount of money, it is necessary to rent referrals.  But nobody has any control over these referrals.  Hence, there is no guarantee for a handsome profit every month. Moreover, as a free member, your earning will be very much limited. To upgrade membership, a lot of money needs to be spent and when there is no guarantee over long-term existence of the business, it is very risky.

However, in my personal experience, I came across a number of signs that tell us when a PTC site is going to turn as a scam site.  This is purely based on my own experience and therefore, it may not be a complete list:

High click rates

If a PTC site offers high click rate on a number of advertisements, this can be an indication of foul play. This kind of business can never survive in the long run.  It will adversely affect their free cash flow and finally lead to their closure in the future. 

Unbelievable deals

This is another indication. Usually before a site becomes a scam, they may come up with a lot of deals like rented referrals at half rates, very cheap membership up-gradation plans etc.  In some cases, they will even offer a 100% cash back of investment in purchase balance.  The members cannot withdraw this as this is in purchase balance.  All these are steps to attract maximum investment from members before closing down the business

Long-term membership offer

This can be an early signal. If a site offers up-gradation packages for more than one year duration, its credibility needs to be tested.  They are trying to give an impression that they will stay forever and members can safely invest in the business.

Sudden abnormal rise in the number of advertisements to click

There is a high possibility that the site has already turned scam and members are using the money they already earned for advertising their other businesses.  They already know that it is impossible to withdraw money from the site anymore. 

Dead community forum

A live forum is a must for any genuine paid to click business.  It shows what is going on behind the doors and also give the freedom to interact with other members.  In most of the cases, before turning into a scam phase the site owners will deactivate the forum first.

Investment in paid to click site is always risky.  But working as a free member demands a lot of time to earn something. So, it is better to do proper research before investing in such sites and be alert for the indications.  You may save your time, effort and money.