Why are passports controlled two times at arrival to Schengen countries?

From time to time I travel from Turkey to the Schengen countries (Germany, Netherlands, Italy etc.). Not all the time, but sometimes I see that our passports are controlled one more time as soon as we get off the plane. This practice was the same even 4-5 years ago.

I wonder the point of the additional control.
Since it is done more careless than the regular passport control, what is the benefit of it?

Best Answer

As been said in comments, there are at least two reasons to do such additional checks right after the plane landed:

search for the criminals (it can be either a concrete person or a general check for unusual behavior)
check for those nationalities, citizens of which need a transit visa even if they do not go outside the transit zone.

I've met such check in FRA, and asked about the reason, and they explained about the transit rules. I've shown them tockets and visas, and that was ok. I wouldn't say that that check was less strict comparing to general check on border, it just being done without background checks in security databases.