Revealing his thinking on political leadership renewal last night, Prime Minister Lee Hsien Loong said it involves striking a balance.
On the one hand, the Government has to avoid abrupt discontinuities. On the other, it cannot risk drifting out of touch by keeping the status quo for too long.
"Otherwise, by the time this shows up in our performance, support and election results, it will be far too late," said PM Lee.
Speaking at an appreciation dinner for three ministers who retired as part of a Cabinet reshuffle last month, he added that Cabinet changes were one of his "most difficult - but important - responsibilities as Prime Minister".
The trio are former manpower minister Lim Swee Say, 63; former communications and information minister Yaacob Ibrahim, 62; and former trade and industry minister Lim Hng Kiang, 64.
"I take stock every year - whom to bring in to political office, whom to promote and who should move on," PM Lee said. "A single round of Cabinet changes is often incremental. But over time, these regular adjustments add up, and substantially alter the shape and composition of the Cabinet."
The latest reshuffle, which saw more fourth-generation ministers taking significant roles, was "particularly difficult" on an emotional level, he said, because of the retirement of the three ministers.
PM Lee on...
MR LIM HNG KIANG
"He knows when to let things be, and allow the free market to make our economy competitive and efficient. He also knows how to step in when the market is not working, to achieve political or social objectives... Hng Kiang is a laconic man - perhaps the only part of him that is unusual for a politician. But his point of view is always rational and incisive. He cuts to the core of issues, calmly and decisively. His proposals are always pragmatic, and with a human touch. That is why I always take his views very seriously."
MR LIM SWEE SAY
"We all know how hard it is to persuade people of the need to increase taxes. If anyone can do it, it is Swee Say... He has done it in hundreds of block parties with his residents in Bedok, to remarkable effect. I asked him whether he would do a video of his pitch, or even a hologram, like Mr (Narendra) Modi in India, to multiply his effectiveness. But he told me, no, it has to be done in person... Now that Swee Say has stepped down as a minister, perhaps he will have time to conduct some master classes, to show younger ministers and MPs how it should be done."
DR YAACOB IBRAHIM
"Yaacob joined Cabinet... just after the Sept 11 terrorist attacks. As Minister-in-charge of Muslim affairs, he provided crucial leadership for our Malay/Muslim community at a moment of anxiety and uncertainty. He felt strongly about what made a good Muslim and a good citizen. On sensitive issues of race and religion, Yaacob always took a principled and sensitive approach. This called for courage and conviction, a willingness to take flak and not just to do the easy thing. I have no doubt that Yaacob's firmness exposed him to criticism, and came at some cost to his personal popularity. But Yaacob held firm, and in doing so made a vital contribution to maintaining our racial and religious harmony."
"I have known them and worked with them over many years - nearly 20 years for Yaacob, and 40 plus years in the cases of Hng Kiang and Swee Say. In terms of ministerial experience, we are losing 70 years of solid, battle-tested experience."
PM Lee paid tribute to each minister in turn. As minister-in-charge of Muslim affairs, Dr Yaacob played a key role in maintaining racial and religious harmony with his "principled and sensitive approach", he said.
Dr Yaacob, who also spoke at the dinner, thanked various groups of people he had met in his career, such as civil servants and ministers.
He made special mention of fellow Malay MPs who worked with him to "bring the Malay community forward", as well as his Jalan Besar GRC teammates.
On Mr Lim Swee Say, PM Lee highlighted his crucial role strengthening ties between the Government, employers and workers, especially during the financial crisis of 2008.
In his remarks, Mr Lim reflected on his career, saying he was grateful to spend the first 20 years of his working life contributing to Singapore's economic competitiveness as a public servant, and the next 22 in politics, working for the people.
"Now, I am very happy to contribute to the third pillar of Singapore's success (which is political renewal), by being replaced by 4G ministers," he said.
Mr Lim Hng Kiang was described by PM Lee as a "steady, absolutely reliable hand overseeing our economy", who revitalised the manufacturing sector, strengthened small and medium-sized enterprises and sealed free trade deals for Singapore.
When it was his turn to speak, Mr Lim confined his remarks to economic issues, urging his successors in the room to remember that when it comes to the economy, "size counts".
"We should grow the economy gradually in keeping with our potential. There are those who think we ought to slow down - this would be a big mistake," he said.
PM Lee, who noted that most 3G ministers, including himself, are in their 60s, said that while the three still have much to contribute, they "graciously agreed to retire, so that... we can make progress on leadership renewal".
"We are still largely in good health, touch wood. We can carry on for one more term, at most two."
The third generation must renew the team while they are vigorous and on top of their game, he said.
The reshuffle allows a new generation of ministers to build on their predecessors's work. "Their success will be our success too. This is stewardship."
As a token of appreciation, PM Lee presented each of the retired ministers with a portrait by local artist Ang Wei Tyng.