  We study the fine-tuning problem on the initial condition of inflation in the
minimal supersymmetric standard model (MSSM), associated with the narrowness of
the slow-roll region. We consider two cases before the onset of the MSSM
inflation, namely, the radiation dominated era and preceding inflationary era.
We find thermal dissipation does not induce additional friction to the
inflaton, so that it does not help enlarge the slow-roll region. We argue
thermal correction to the potential in the preceding radiation dominated era
and quantum fluctuations in the preceding inflationary era disturb field
configuration and prevent the MSSM inflation unless some specific preinflation
history is realized.
