Sometimes due to biotic/abiotic factor climax remain in a particular seral stage (pre climax) without reaching climax. Do you agree with this statement. If yes give a suitable example. 

This entire sequence of communities that successively change in a given area are called sere (s). All the biotic and abiotic factors play crucial role in this transition process and thus enable a community to reach the climax. If biotic and abiotic factors are not supportive enough for climax then the community may remain in a particular seral stage without reaching the climax. Presence of sparse vegetation at table top mountain can be one example of a community in seral stage. The community at the table top mountain may be in a stage in which only ferns and mosses may be present, in due course of time, it would pave way for higher plants.