Difficulty Bomb

The term ÔÇťdifficulty bombÔÇŁ refers to the gradual increase in Ethereum┬ámining difficulty as part of its migration to a┬áProof of Stake system.
When mining, users guess at the solution to a puzzle that the protocol sets out. The puzzle is designed so that it takes a fixed amount of time for miners to solve it (10-20 seconds in Ethereum). It stands to reason, however, that the more users guessing, the faster theyÔÇÖll find the solution. To remedy this, the protocol increases the difficulty of the puzzle when┬áhashing power is increased.
Ethereum uses this style of┬áconsensus algorithm, but it also includes a difficulty bomb, which increases the overall difficulty at specified block heights. In turn, such an increase decreases the profitability of mining ÔÇô this is the intended effect. As time goes on, it becomes exponentially harder to generate blocks, and rational miners will abandon the practice. Ultimately, the difficulty bomb leads to the so-called ÔÇśIce Age,ÔÇÖ where it becomes so difficult to mine that the chain is effectively frozen.
This mechanism is designed to eliminate┬áProof of Work, in line with EthereumÔÇÖs current roadmap. The network is expected to transition to staking in the future ÔÇô the difficulty bomb seeks to dissuade anyone from continuing to generate blocks on the old chain. Amongst other things, this could prevent the chain from being split into two contentious┬áforks.

It has a secondary effect of preventing the stagnation of development on the Ethereum chain, as developers must frequently upgrade it to prevent it from becoming unusable.