Pronunciation and misunderstanding; is it me?

I thought I had figured out how to maximise student participation with Quizlet, in & out of the classroom, but I happened across another cool angle during the week.

Students finishing tasks quickly while their buddies are still working presents the teacher with a micro management problem; give them a new task that will overlap? Let them kick their heels and wait? Doing a quick task on Quizlet on an iPad is a solution - extra practice or review on related vocabulary for example, without having to relocate (to a PC). It's quiet, so not about to distract the others, but looks fun and encourages to others to hurry up & potentially have a go too.

Working with full phrases (rather than single words) also brings in punctuation - capital letters, apostrophes, spaces - to simple spelling. Typing takes time, counter-intuitively, as learners are not familiar with a keyboard layout. Still, a relevant skill to acquire.

This is where the "Aha!" moment arrived, though (I was trying to help from upside down & failing!) Use the mic and dictate the response.

And then the fun started, as the programme's interpretation of what it had heard produced other than what the students had said. Or thought they had said. Their reaction = the iPad must be deaf, or it can't spell, or it's just stupid ("We've said the same thing 5 times already, and it is wrong again!").

I let them keep trying until it was obvious there was quite a bridge missing. Students' pronunciation (elision or not, hard consonants 'missing', misplaced stress, false starts, intonation?) and my acceptance/perception of their usual utterances (ie my ear tuned to them & our shared context) perhaps allowing less than ideal output? The software second guessing utterances into grammatical structures (with no contextual base, obviously!) - its initial interpretations did 'adjust' as the speaker finished a phrase...

English: logo of quizlet (Photo credit: Wikipedia)

"You do it then!" was the 'we've had enough'
and to their satisfaction, my attempts were equally mangled!

So, what's the problem?!