Is there a word/phrase to describe an action which leads to it being pointless?

Solution 1:

By using the wood, you have obviated the need to store it.

Building a container to store the material you'd use to build the container is a self-obviating action.

obviate ˈɒbvɪeɪt/ verb verb: obviate; 3rd person present: obviates; past tense: obviated; past participle: obviated; gerund or present participle: obviating

remove (a need or difficulty).

"the presence of roller blinds obviated the need for curtains"

synonyms: preclude, prevent, remove, get rid of, do away with, get round, rule out, eliminate, make unnecessary, take away, foreclose, avoid, avert, counter

"the settlement obviated the need for the separate cases to be heard in court"

avoid or prevent (something undesirable).

"a parachute can be used to obviate disaster"

Solution 2:

There is 'self-defeating':

Self-defeating - adjective

1 - serving to frustrate, thwart, etc., one's own intention or interests: His behavior was certainly self-defeating.

www.dictionary.com

Solution 3:

I think self-defeating is close, but I would use the phrase defeats the purpose instead.

However, I do not quite agree you building the shelving was pointless. You ended up having cool new shelves instead of random bits of wood sitting around.

Solution 4:

This strikes me as a classic Catch-22.

A situation in which a desired outcome or solution is impossible to attain because of a set of inherently contradictory rules or conditions

The term was coined by Joseph Heller in the comic novel Catch-22, and is such a useful idea that logicians have formalized and adopted it. It's also entered common speech. I think it's sometimes misused to mean, in general, 'an inescapable situation' but OP's case fits the more precise definition.

The book itself provides several examples of Catch-22. Here are some:

1. In order to be excused from combat duty, you must be declared insane. However, in order to be declared insane, you must request a psychiatric evaluation, which only a sane person (who doesn't want to die in combat) would do. Thus, the very act of seeking an insanity diagnosis prevents such a diagnosis.

2. A prostitute (who has sex for money) refuses to marry any man she deems crazy. Her definition of 'crazy' is any man that would marry a woman who has already had sex. The conditions logically preclude the possibility that she will ever marry a man.

The Wikipedia page on Catch-22 in logic gives a more concise example:

3. To apply for a job, you need to have a few years of experience; but in order to gain experience you need to get a job.

I think OP's case is even neater:

4. In order to store the wood, you must build a shelf; but in order to build the shelf you must use the wood.