There are four significant variables which introduce uncertainty: ASICs, difficulty, fiat exchange rate and mining operator solvency.

One reason may be that the main post, one page one before the dividend record, has not been upgraded in a long time. Consequently, potential investors have to sift through 12 pages in order to get an accurate view of what is currently happening. As a result, they may be unaware of the ASIC upgrade plan, solvency of amazingrando relative to other mining bonds, etc.