Why are so many politicians quitting at next year's election?

So far, 22 MSPs have indicated that they will not stand in next year’s election.

It seems like a lot, especially when it includes some big names and some of the most experienced politicians in the country.

The list includes former first minister Humza Yousaf, and yesterday Cabinet secretaries Shona Robison and Fiona Hyslop announced their retirement plans.

The Conservatives are losing Liz Smith, one of their most respected MSPs.

Labour is losing former leader Richard Leonard, who has proved a formidable chair of the Public Audit Committee, and Lib Dem Beatrice Wishart is going too.

And there will be more to come, I have a list of at least another 15 with question marks, and some of them are pretty big political names.

Former first minster Nicola Sturgeon is yet to say whether she will run for Holyrood in 2026. Getty Images

So far 22 out of 129 announcing their retirement might seem like a lot, but it is far from unusual. Last year at the General Election, 132 MPs announced their retirement before the ballot.

Ahead of the 2021 Scottish Parliament Election 34 MSPs retired including seven who had been SNP Cabinet secretaries, two former Labour leaders (Johann Lamont and Iain Gray, just to save you looking them up) and former Conservative leader Ruth Davidson.

In 2016, 24 MSPs retired, Including former first Minister Alex Salmond and former justice secretary Kenny MacAskill, who might be about to attempt a comeback as an Alba candidate.

Former Conservative leader Annabel Goldie went, as did former Labour Cabinet ministers Malcolm Chisholm and Hugh Henry and former Presiding Officers Alex Fergusson and Trish Marwick.

In politics, like every other job, some people retire because they are simply of an age to retire or would come to retirement age during the next parliamentary term.

Others go because of ill health and changing family circumstances.

I think it is increasingly common for people to go because they are exhausted; being an MSP, if you do it right, is hard work with long hours.

Inevitably there a few who go in disgrace. And all of that is even before political party members have their say in selection battles and voters have their say in elections.

I am not surprised that so many have announced plans to step down at the 2026 Scottish Parliament Election, and don’t be surprised when that number increases significantly over the next few weeks as they tell their local party members and then the rest of us.

What it means though is the loss of significant figures, great experience, and political substance, but that happens at every election (see above).

It could mean a tricky reshuffle for First Minister John Swinney in the coming months.

Does he keep leavers in his Cabinet, as Nicola Sturgeon did with Jeanne Freeman in 2021, or does he ditch them and look to the future.

If he hadn’t become First Minister, Swinney would probably be announcing his retirement plans right now.

Instead he’s going again.

You would expect him to be re-elected in Perthshire North next year, just as you would expect Labour deputy leader Dame Jackie Baillie to be re-elected in Dumbarton.

They could be the only two remaining MSPs from the first Scottish parliament in 1999 by May of next year.

That’s a long shift, I know, because I’ve been here that long too.