Everyone experiences a few lagging torrent transfers, that never finish or go above 99%.  They stay unfinished and tick, tick, tick at 69 bytes or less per interval / second and there are 5gb left to finish.

Auto refersh and auto search are features that need be incorporated as well as some performance measurement feature, so that torrents do not last 8 days and longer and never get past 40% or some other outlandishly never-to-finish slow pace.

What can be done presently?
why does this happen?
what is the cause and solution?

at this point, I would settle for an open discussion on this topic.  Perhaps it has been addressed, under different thread or by a different title, but the solution remains the same.

so, in short, why do some trackers / torrents take long past forever?

some torrents do not finish because the seed gives no bandwidth to the torrent or there is no seed.