Wikipedia:Please discuss on talk page first

Many Wikipedia articles have hidden notes requesting or requiring that any potential changes to the articles be proposed first on the talk page: "Please discuss all changes on the talk page first" or "The lead to this article is the product of substantial consensus. Do not edit the lead without discussing your proposed changes".

Do I have to follow these instructions?
No, not for articles. Despite the purported existence of these "rules", there is no requirement under Wikipedia policies to discuss edits on the talk page first for articles.

Neither an editor or a group of editors who watch an article and contribute regularly nor the creator of an article own an article and have the right to "approve" or "disapprove" of any edits to the article before they are made.

The WP:Be bold editing guideline actually encourages editors to boldly make changes. It doesn't say "Propose your edits on the talk page and seek approval first".

Wikipedia Manual of Style even says some uses of hidden text inappropriate...
The WP:MOS editing guidelines on "Inappropriate uses for hidden text" say that hidden text should not be used for:
 * Asserting ownership of an article;
 * Telling others not to edit an article, period;
 * Telling others not to perform certain edits to a page, unless there is an existing guideline or policy against that edit.
 * When it is a mere local consensus that a certain edit should not be performed, the hidden text should be worded more softly to suggest to the editor to consult the talk page (or archive page if appropriate) for the current consensus prior to making the edit. Since consensus can change, it is inappropriate to use hidden text to try to prohibit making a certain edit merely because it would conflict with an existing consensus.

Be bold!
Almost any editor can edit almost any article on Wikipedia, including a Featured article or even a Featured article on the main page, just by clicking the "Edit this page" button (the exception is articles that are "locked down" by administrators). The Wikipedia policy on editing Featured articles, at WP:OWN, does not require changes on Featured articles to be discussed first on the talk page; it says "Editors are asked to take particular care when editing a Featured article; it is considerate to discuss significant changes of text or images on the talk page first." While it is considerate to discuss significant changes, it is not required, even for a Featured article.

In fact, "being bold in making changes" is a Wikipedia editing guideline. Being bold in making edits is part of an editing practice known as Bold-Revert-Discuss (or BRD). In the BRD cycle of editing, an editor boldly changes an article, the changes are reverted by other editors, and then there is a discussion on the talk page. An editor acting in good faith can make edits to articles, including major edits which change the lead, add sections, and add content, without seeking talk page approval.

Note of caution
The statements made above, encouraging editors to directly edit articles, apply solely to Wikipedia articles. Wikipedia policies and guidelines should not be directly edited (with the possible exception of fixing an obvious minor error, like a duplicate period). Instead, editors should propose changes to Wikipedia policies and guidelines on their talk pages, and seek consensus from other editors before editing. This is normally a lengthy process, which requires a great deal of discussion. Editing a Wikipedia policy or guideline directly, without prior talk page discussion, could lead to WP:Discretionary sanctions.