We hear this a lot in the resource industry. So here is one of the many reasons.
People are promoted into training roles from operations and the put through a Cert IV in Training and Assessing. Then they are expected to know how to be a trainer. It takes 4 years of university to be a high school math teacher but you can be in charge of training a person to operate a million dollar piece of machinery that has the potential to kill multiple people at one time with a Certificate IV which might teach you how to make a powerpoint presentation – if you do it through a reputable provider.
Companies need to invest time and resources into their trainers if they want good trainers. It’s as simple as that.