Boris Becker spent a few months behind bars and he explained the experience as tortourous and dangerous as you have to be alert all the time.
Becker ended up behind bars after breaking the law and getting convinced for it yet he was released early. The time that he did spend being bars was not a pleasant experience for him. He has spoken about the dangers of being in prison before but refused to go into detail once more when asked about it:
"Yes, it's dangerous. You can only share [it] with other inmates because someone on the outside world wouldn’t believe it. So yes, it’s dangerous. You have to
always look around your shoulder, you don't know who is in the next
cell."
He further explained:
“Another difficult moment was I was surrounded by murderers, rapists,
drug dealers and people smugglers. We are all inmates and we all share
the same canteen, so [it’s about] how you deal with that.”
And recalled what he thought about during that time:
"You have to survive day-to-day. Every day is
dangerous. Prison is a very tough place and is a real punishment, anyone
who says it is not the case are lying. You have to surround
yourself quickly with the strong ones inside as you need protection,
because you need to survive week-by-week."