Don't you think that sometimes failure can be the worst thing.

Failure can be catastrophic, life changing/life ending, so yes it can be the worst thing sometimes, but it can also be the best thing. Say a project you're working on at work fails...Ok, now you know one more way not to do it. Evaluate, plan, strategize and move forward to the next try. We don't learn much from success.

Like you prepare very well for something but still end up failing, still this type of failure is essential for success?

See above. Failure is the reason we have so many of the useful things in life right now. Accidents and failures. The people just learned from them and did things differently.

Want to succeed more? Fail more! (It means, learn, plan again, and retry.)

I don't like failure at big levels as they can hit you very badly.

Yep, and then you should be taking some massive fucken action to make sure you make the changes required to succeed at that thing. Massive action man, massive. Fucking around with activities in which there's little effort will bring little results, if any at all.