PVS-Studio warning V560 for MongoDB

void doRemove( OldDataCleanup& cleanup ) {
  int it = 0;
  while ( true ) {
    if ( it > 20 && it % 10 == 0 )
    {
      scoped_lock ll(_workLock);
      if ( ! _active ) {
        cleanup.doRemove();
        return;
      }
    }
    sleepmillis( 1000 );
  }
}

'it' doesn't change.

This suspicious code was found in MongoDB project by PVS-Studio static code analyzer.
Warning message is:
V560 A part of conditional expression is always false: it > 20. d_migrate.cpp 565

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/