Time seems to fly by on a project, especially with agile development methods being so prevalent these days. If you miss a deadline by even a whisker, things can turn ugly. If time is so tight that you cannot do UX research before the launch of a product, do it post launch, then quickly fix the issues you discover as the project progresses.
If a stakeholder or client isn’t allowing you time to plan for research, be smart and analyze whatever research data is already available. Be prepared to run usability tests and make adjustments to the design later on. However, rather than skipping UX research altogether because of time and budgetary constraints, consider employing the following research methods instead: