To produce a cloud, there must be machinery inside it, regardless such machinery is visible or not; with color or transparent.
If rain was the consequence of vapor condensation, the cloud would be everywhere above the sea. Not to mention the altitude needs to be much higher to allow condensation occur by certain quite a long duration.
Why?
You have made a bold claim with no justification at all.
The simplest answer is the turbulence of the atmosphere. You have some regions of the atmosphere going up, in thermals, which would take warm, moist air up to condense. You then have other regions going down.
Why would clouds form in the region going down?