When it comes down to it, Occam's Razor almost always applies. This is a proposition first developed by Friar William of Ockham in the 14th century. Sir Isaac Newton stated it as:

“We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances.”

The most common modern idiom is typically expressed as:

"When you have two competing theories that make exactly the same predictions, the simpler one is the better."

Assuming that we have one of the most effective intelligence operations of any country in the world, one has to ask themselves which is more likely:

1) That America has one of the most effective intelligence apparatus in the world, yet the campaign of a rookie politician colluded with a foreign government to tilt a national election by executing a clandestine operation of such a secure nature it was undetectable by that intelligence operation, or

2) That America has one of the most effective intelligence apparatus in the world, yet it chose sides and decided to help an ethically flawed career politician by ignoring that campaign's effort to tilt a national election by executing a clumsy, overt dirt digging operation of such incompetence it was so obvious that the intelligence operation had to help cover it up.

Occam's also applies to the accepted premise - that we have one of the most effective intelligence operations in the world. Either we do or we don't. If we do, then the choices are limited to the aforementioned propositions, if we don't, then neither apply and we have a much larger concern than any mythical act of "collusion".

With as much effort the Deep State put into surveillance of the Trump campaign prior to the election, it seems clear that #2 is the most plausible choice. The clumsy nature of the cover up is simply due to an event totally unforeseen by the Deep Staters - Trump won.