The notion of allowing a defendant to post bail and be released from jail is a risky concept to some people. In their minds, it means another criminal, who is possibly dangerous, is out on the streets, posing a threat to the public. These type of people only see this negativity of bail, they do not see the advantages of bail.
Bail also further entices a defendant to appear in court on their scheduled day, rather than skipping town. The court agrees to release the defendant from custody while the defendant agrees to pay a large sum of money, which they can potentially get refunded back to them as long as they show up for court. This bail money could be their own, or it could come from friends and family, in which case, they are also risking their relationship with their support system. They do not want to jeopardize their relationships, so they will be more likely appear in court as scheduled.
Finally, by posting bail, a defendant can return home to live and work. They will constantly be surrounded by supportive loved ones. They will refocus their energy and responsibility to get their life back on track. They will be able to provide for their family once again.
There are plenty of advantages to bail and why it is a good, constitutional concept to have in place.