title: Why you should not use Observable.create
body: <p>I've seen in many Rxjava tutorials , the usage of <code>Observable.create</code> method to create an Observable is not encouraged. Instead better to use <code>Observable.fromCallable</code> or <code>Observable.just</code> to emit a single object. Use <code>Observable.create</code> as a last option. Why is that? One of the problems is handling of back pressure. Is there any other risks by using <code>create</code>? Can anyone please explain it with some examples for better understanding? I didn't get a proper explanation for this question from any of the tutorials , that's why I'm asking here. Thanks in advance</p>