In my world, magic is based on the use of magical words passed down as part of a long-forgotten language. The spells are "self powering", they do not cost the user anything.
The catch is that results will vary dramatically based on several factors including:
- The mental state / concentration / emotional state / confidence of the user
- Whether or not (s)he has used that spell before
- Whether (s)he got the pronunciation right
For example, a drunk who has never perform the fire spell before might use the magic word for burn, and only set fire to a single blade of grass. Whereas a professional pyromancer who has been meditating for several hours might be able to incinerate an entire army using the same spell.
My question is whether this magic system is chaotic enough to encourage the advance of technology. Or will the presence of magic, however unreliable, still discourage technological advancement?