A very niche rant
alksjhdfalksjdfh OKAY OKAY OKAY so there was this one thing in grad school that made me go absolutely feral which was people saying, "you can't write a goal at 50% accuracy, ThAt Is ChAnCe." And when I say people, I mean fucking clinical supervisors and professors at my Master's program.
The thing is, though...the vast vast majority of the time it just fucking isn't. If I am trying to teach someone to say their /r/ sound correctly, they might start out at 0% accuracy. Because they say it correctly exactly never. That kid being able to say it with 15% accuracy would be a great improvement! 50% would be something to throw a party about! Now obviously you don't want 50% to be your end goal. Like definitely keep going until it's up pretty high.
The *only* scenario where a speech goal written to 50% accuracy is actually the same as chance is if the goal is formatted like this: Child will identify synonyms with 50% accuracy given a multiple choice format (field of 2).