The deterrent effect of short-term sentences is lost on criminals who are jailed time and time again, a report has found.
While prisoners serving their first sentence were "unanimous" that it would also be their last, those who had served several sentences already said time behind bars was "relatively easy because it was something they were used to".
Justice Secretary Kenneth Clarke wants to keep prison for the most serious offenders and cut the number of jail terms under 12 months as part of a "rehabilitation revolution" which would result in thousands of offenders avoiding jail.
The report, published by the Howard League for Penal Reform and the Prison Governors' Association, said the experiences of prisoners and staff showed "the potential deterrent effect of serving a short prison sentence is lost" for repeat offenders.
Prison was also easier than it used to be, with better facilities and improved relationships with staff, making some offenders prefer a short time in jail over a community sentence, which they said could drag and take time to complete.
"Those serving their first prison sentence were unanimous that this was their first and last prison sentence," the report said. "These prisoners were usually the most negative about their experience of serving a short prison sentence."
But it added: "Those who had served several prison sentences were unanimous that this prison sentence had not been a shock. Many also indicated that they would rather serve a short prison sentence than complete a community order."
The report, by Julie Trebilcock of Imperial College, London, also found that serving a number of short prison sentences may reduce the ability of prisoners to take responsibility and led many prisoners to "regard their return to prison as inevitable".
A Ministry of Justice spokeswoman said: "All sentences must punish offenders effectively as well as address the causes of their offending.
"Short sentences remain an important option for the courts, however, community sentences can also be an effective way of punishing and reforming offenders."