It's an odd spell to commit to using every turn, even at low levels. If you're fighting against something dangerous, you're better off casting Magic Missile or Chromatic Orb every turn for a significant increase in damage. On the other hand, weak enemies die before this spell can get enough hits in for the 10 turn auto-hit to pay off. I think the auto-hit is what makes it suck, because there is no point in committing your action to weak guaranteed damage for 10 turns against a single target.
For me, the payoff is (or should be) the fact that it doesn’t require use of a new spell slot to reactivate. So I think you were right in an earlier post to compare the benefit of reactivating Witch Bolt on a subsequent turn to use of a cantrip and to point out that it’s probably not going to beat that as an option for most builds, at least after level 5 once the possibility of additional cantrip damage is almost always going to be worth the risk of missing.
I do agree that the fact that you’re probably not going to get more than two or three rounds of use out of reactivation at these lower levels needs to be taken into consideration when deciding whether to use it rather than a one-off spell that might be expected to do higher initial damage, but don’t see this as a problem in itself. But once damage on subsequent rounds becomes irrelevant, which it does if reactivation is never going to be the best option, I agree that it becomes more of a straight competition between the initial damage of Witch Bolt treated as a one off spell and the other one-off spells that we could cast instead at the same level, and unless picked for RP reasons it’s not going to do all that well there.
