No exercise credit for doing a 30 minute walk

Because you need to do the walk at a "brisk walking pace"

According to apple support, for the activity ring to register your workout (for

outdoor walk or exercise ring) you need to maintain a speed of approx 3.3 mph

or faster,this is their definition of a "brisk walk".If you slow down or pause the

watch will stop tracking your movement as exercise credit,it will still measure

your steps and calories burnt but will not give you any credit towards the

exercise ring or workout app.A brisk walk speed is different for everybody as the

watch takes into account your age,sex,weight and heart rate which why it is

important to calibrate the watch when you set it up from new,the idea being

that you're being encouraged to put more effort in to walk faster and to get your

heart beating faster, if you just walk at a slow pace then you are not going to

improve your fitness or get all those award badges that we all seek.

Ok then tell apple your thoughts;

Feedback - Apple Watch - Apple

You can do your walking workout as "other" workout,this gives you 1 minute of credit for every minute you walk regardless of speed and also credits you with calories burnt.