Pressing Tab should move focus to the next cell to the right. That is the expected behavior, and it works reliably across millions of spreadsheets every day. When it suddenly jumps to a different sheet instead, something has gone wrong. The user who posted this question is not confused about how spreadsheets work. They have checked for formulas, confirmed no hidden references exist, and isolated the issue to one specific cell in one worksheet of one document. That level of precision rules out user error. It points to something in the software itself.
The most likely explanation is a corrupted or misconfigured setting buried in the workbook's internal metadata. Spreadsheet files store more than just the grid you see. They carry formatting rules, print area definitions, named ranges, and occasionally orphaned behavior flags that no standard menu exposes. When Tab starts treating a single cell as a hyperlink to another sheet, the cause is almost certainly one of those invisible artifacts. It is not a glitch in the sense of random failure. It is a hidden setting that the user never intentionally enabled but that the file now enforces.
This matters because it reveals a fundamental limitation of traditional spreadsheet tools. When something breaks in a way that cannot be explained by formulas or visible configuration, users have no diagnostic path. There is no error log, no inspector for cell-level navigation rules, and no support channel that will accept "Tab moves to Sheet2" as a valid ticket without hours of back-and-forth. The user in this case did the right thing by documenting the exact conditions. They will likely receive guesses ranging from "reboot your computer" to "reinstall the software." None of those will fix the underlying cause because the cause is structural, not environmental.
An AI-native spreadsheet does not hide these behaviors. Every action, including navigation, is a traceable operation. If Tab jumps to another sheet, the system can explain why in plain language. It can show the rule, the source cell, and the target. It can offer to remove the behavior or turn it into an intentional workflow. That is the practical difference. The user asking "What gives?" should not have to accept mystery as part of the tool. They should get an answer. That answer exists when the software is designed to surface its own logic instead of burying it.