Short answer — for short international trips the most consistently reliable low-cost carriers (LCCs) tend to be region-specific. Good picks depending on your route are:

• Middle East / GCC: Jazeera Airways (Kuwait-based) — strong punctuality and high OTP locally, plus convenient short-haul network from Kuwait. (traveldailynews.com)
• Middle East / North Africa hubs: Air Arabia (Sharjah) — a large regional LCC with generally solid operational performance on short routes across the region. (statista.com)
• Europe (short international hops inside Europe): Iberia Express, Vueling and easyJet — Iberia Express led LCCs for punctuality in 2024 and Vueling and easyJet also rank well for short European hops. (euronews.com)
• Southeast Asia / Asia-Pacific: AirAsia group (including Thai AirAsia and Indonesia AirAsia) — consistently among the better-performing LCCs in the region for on‑time performance. Jetstar is a solid choice in Australia/Oceania. (newsroom.AirAsia.com)
• Latin America (if relevant): GOL and Azul — ranked high for punctuality among LCCs operating many short international/regional sectors. (samchui.com)

Notes and quick tips for choosing a reliable LCC for short international trips

• Look at on‑time performance (OTP) for the specific route/airport you’ll use — an airline can be punctual overall but perform poorly on a particular airport pair. Cirium/industry OTP reports are the usual source. (euronews.com)
• Beware recent operational issues: some LCCs (e.g., Wizz Air in 2024–2025) have faced fleet/engine disruptions that affected reliability — check recent news for the carrier before booking. (reuters.com)
• Frequency matters: on short trips higher daily frequency reduces impact of a single delay or cancellation (you can rebook the same day). Prefer carriers with multiple daily flights on your route.
• Airport and slot congestion: flights at congested airports (main hubs, peak times) are more likely to be delayed regardless of airline. Early-morning flights usually have better OTP.
• Check the airline’s cancellation/compensation and rebooking policy for international connections — a very cheap fare with weak protection can cost you time and money if disruption occurs.

If you tell me the specific short international route(s) you’re considering (for example: Kuwait–Dubai, Kuwait–Istanbul, Kuwait–Cairo, Kuwait–Doha, or Kuwait–Bahrain), I can check the most recent on‑time and cancellation performance for the carriers that fly those routes and give a ranked recommendation.