This is entirely the situation with most aoe throw skills. They only cover a small area, dont follow a target, and take too long to execute. I often see them as a way to force the enemy to move which is actually quite handy at times. However, most of them have a long animation and thats my big issue. The long time for the animation always kills the usefulness as it kills your dps. The idea behind these is to use against a target to force them out of hiding, stop them from using a skill, or slow their dps. But when it kills your own dps it does more harm than good.
Take Ghoul for example. His improvised bomb is actually a decent skill. it forces someone to move, the bomb stays in that spot in case they move back (area denial), and most importantly - the skill is executed very fast. Its one I use often in pvp if i use him. His Molotov OTOH is far less useful in pvp. It has neat potential with a lingering effect, but the animation is too long.
Becks ability, while not the worst in terms of start up time, is bad. Simply because shes a high level dpser. Its never worth wasting the time for this skill on her.