But in practice this is not true. There are some excellent schools and some excellent certificates. There are also some crooked schools and worthless certificates. It doesn't matter if it is a traditional school or an online school. There are saints and sinners everywhere.
Some schools have one or maybe two teachers.
At ICAL we have over fifteen highly qualified teachers and you can read about their qualifications and teacher training background here . Make sure the school is not a rip-off. Take a look at John Bear's excellent independent site Degree. Net to make sure the school is not bogus. Click here to read ICAL's policy on Refunds and Privacy.