Apple iPhone is known for the extent of security it provides from the harmful elements such as malware and virus. The absence of customization options restricts its users from executing thorough changes to the phone's software. Some users, who aren't in full favour of the secured system by Apple, attempt making unauthorised changes to their iPhone. However, here's Apple's explanation why you shouldn't do that.
Unauthorized modifications to iOS (also known as "jailbreaking") bypass security features and can cause numerous issues to the hacked iPhone, iPad, or iPod touch, including:
Security vulnerabilities: Jailbreaking your device eliminates security layers designed to protect your personal information and your iOS device. With this security removed from your iOS device, hackers may steal your personal information, damage your device, attack your network, or introduce malware, spyware, or viruses.
Instability: Frequent and unexpected crashes of the device, crashes, and freezes of built-in apps and third-party apps, and loss of data.
Shortened battery life: The hacked software has caused an accelerated battery drain that shortens the operation of an iPhone, iPad, or iPod touch on a single battery charge.
Unreliable voice and data: Dropped calls, slow, or unreliable data connections, and delayed or inaccurate location data.
Disruption of services: Services such as iCloud, iMessage, FaceTime, Apple Pay, Visual Voicemail, Weather, and Stocks, have been disrupted or no longer work on the device. Additionally, third-party apps that use the Apple Push Notification Service have had difficulty receiving notifications or received notifications that were intended for a different hacked device. Other push-based services such as iCloud and Exchange have experienced problems synchronizing data with their respective servers.
Inability to apply future software updates: Some unauthorized modifications have caused damage to iOS that is not repairable. This can result in the hacked iPhone, iPad, or iPod touch becoming permanently inoperable when a future Apple-supplied iOS update is installed.
Apple strongly cautions against installing any software that hacks iOS. It is also important to note that unauthorized modification of iOS is a violation of the iOS end-user software license agreement and because of this, Apple may deny service for an iPhone, iPad, or iPod touch that has installed any unauthorized software.