The reason for trimming an aircraft is to reduce or eliminate permanent control forces.
That's true but I would say the primary purpose of the elevator trim system is to set to aicraft angle of attack which (for a given w&b configuration) sets the speed at which it will fly.
The likely reason so many people stall and spin (and kill themselves) is because nobody told them to trim for the desired speed.
Once one discovers this little secret, flying suddenly becomes so much easier because one is no longer fighting the aeroplane. The trim sets the cruise speed, and the engine power merely controls the rate of climb/descent.
Of the 10 or so instructors I had, only one came up with this explanation. All the rest would just say the trim is to take out the elevator control force.