Oil Reserves mean little to the actual economy and isn't always the best to exploit fully even during the good times, here is a book explaining WHY its a stupid idea to invest in Latin American oil after Saudi Arabia and OPEC became a dominant player from the view of another country with an oil company who tried and failed to take on OPEC, Mexico. It also goes and explains the greater role oil had in Latin politics. Its a good read.
This book states, in clear terms, that Venezuela was fucked from the very moment they joined OPEC and believed oil was the solution to everything and OPEC would thrust them to become king of the planet. OPEC had a bias towards muslim countries, which Venezuela was not. OPEC wanted to create an oil cartel that made it suicide to try to outproduce, or out sell their favorite members. Venezual was not one of their favorite members.
Venezuela was viewed by OPEC exactly the same as Helga Phugly was viewed by the Debbies in the Oblongs.
Venezuela is literally your dweeb little brother your mom forces to take with you to a concert with your cool friends.
There is a reason the large Latin American oil reserves are left untapped. Saudia Arabia and its friends invested in over-production to discourage an expansion in oil extraction around the world, and flooded markets with oil to kill competitors like its doing now to American oil.
Or shut the spigot off entirely when they wanted to punish a country, like the US in 1973.
So Venezuela was convinced that with OPEC and the oil reserves that they'd be rulers of the planet forever.
The book however shows Mexican diplomats laughing at how gullible Venezuela was in believing that OPEC had its best interests at heart after Mexico pulled out of joining OPEC, and predicted economic collapse in Venezuela in the coming decades. In the 1980s.
Venezuela has bought entirely into the "WE GOTZ DA ERRRRRL" meme peddled by Saudi Arabia to the point both Left and Right still think their mediorce quality oil will make them a super power.
As 1980s Mexicans said, Oil isn't the answer to everything.