I now buy only organic garlic. It is always typical garlic white, just as the non-organic stuff I used to buy.
However, my most recent purchase (of 3 days ago), is a different story. First use the day of purchase yielded one clove, rotted to the point that its sac collapsed, a common occurrence under long term storage, so no big deal. Other cloves I used at that time were fine.
This morning I found another much as described by OP above. This particular clove is not sticky, not particularly soft/squishy, but brown, translucent, and putting off a heavy garlic odor, as opposed to the typical clove which does not smell strong until cut or crushed, in other words, damaged in some way. So in my case at least, I believe bruising is the answer. Examination of the outer clove surface seems to support this; it shows a line of demarcation of damage, where deterioration is not quite complete on the left (also incomplete on the inside), so damage seems to have occurred on the right side of the clove and deterioration process is moving left and inward.
I'm tossing the clove out of precaution, though I believe it is probably fine.
If, in my case, the whole head had been affected, I would think waxy breakdown, but I offer this observation as another option for those coming to this site for answers.
I appreciate my new-found knowledge about waxy breakdown. Thank you rackandboneman!