Obscurity is also caused if, when you intend to insert a number of details, you do not first make your meaning clear; for instance, if you say, "I meant, after telling him this, that and the other thing, to set out," rather than something of this kind "I meant to set out after telling him; then this, that, and the other thing occurred."
It is better to be concise and clear rather than long-winded and obscure.