When installed properly, there will be some give to the mesh due to the fact that it needs to be flexible in order to retract. However, if installed incorrectly there may be too much flexibility.
Follow these guidelines to minimize any issues:
Make sure to always lock the retractable safety gate by pushing and turning the lock. This will keep the mesh taut and help prevent your child from pushing the mesh out.
Be sure the base of the baby gate is sitting on the floor and is not mounted up off the floor at all. When in use there should be no more than about 1/4" gap between the bottom of the mesh and the floor.
If you have the retractable safety gate mounted near a step, make sure the mesh is at least six inches back from the edge of the step. Being close to an edge can create a gap that babies may be able to push through.
When the mesh is extended and locked, both the top and bottom should be tight with no slack. If there is slack in the bottom, it probably means the bottom brackets are spaced too close to each other (compared to the upper brackets). Adjust the brackets so the distance between them across the opening is identical.
To apply a slight amount of additional tension before locking the mesh in place, tighten the roll of fabric (no more than 1/8 of a turn), and then lock the gate.