Transaction failures are a frequent hurdle in Sui, often due to gas shortages, equivocation (using the same coin for multiple tx), or shared-object conflicts. Sui’s parallel processing enables high TPS (up to 300,000 for simple tx), but complex interactions can fail, as seen in user reports of aborted tx from invalid inputs or overflows. These issues arise from Move language’s strict type system or network congestion, impacting DeFi swaps, NFT mints, and staking. Failures waste gas and time, eroding trust. Root causes include insufficient validation in contracts or user errors like reusing gas coins. Step-by-step solution to troubleshoot and prevent transaction failures:

1. Diagnose the Error: Use Sui Explorer to input your tx hash and view details. Common codes: EInsufficientGas (low balance), EObjectLocked (equivocation). Check wallet logs for specifics.
2. Verify Gas and Inputs: Ensure your wallet has >0.001 SUI for gas. In Sui Wallet, merge coins if fragmented. For devs, use SDK’s estimateGas to preview costs before submission.
3. Avoid Equivocation: Select unique gas coins per tx. In code, implement coin selection logic to split/merge coins automatically. Test on Devnet.
4. Handle Shared Objects: For conflicts, use Programmable Transaction Blocks (PTBs) to batch operations, reducing locks. Devs: Design with owned objects over shared for parallelism.
5. Retry and Optimize: Resubmit with higher gas if failed. Optimize contracts by minimizing computations use unchecked math only if safe, as per Move guidelines.
6. Audit and Test: Run unit tests with sui move test. Use linters for warnings on potential aborts. Post-failure, update contracts via upgrades.