Sage's data is stored internally as a number of related databases - and the more data in them, the longer some reports can take to run (and the more scope there is for something to go wrong, with an error creeping in; a data corruption).

Archiving allows you to retain a prior year's accounts data in an easily accessible form, while pruning the 'live' data to keep the potential for slowness or mishaps to a minimum. (Before the 'archiving' option was added, the only way to access previous year's data if you also wanted to prune the live data would be to restore backups).

That said, for some companies, the amount of data they build up in Sage simply isn't that much, so neither is a significant problem.

(As long as adequate backups are kept!)

I'm as bad when it comes to back ups, and driven people mad with it.

Some of them have since learned their lesson - when they were bit in the bum by their own lack of back ups when things went wrong. Although one of those, having learnt their lesson and became very good about backing up, has eventually fallen back into old habits. :/

It's closely related/very similar to the perennial security problem: The balance between 'convenience' and 'security' - the more you have of one, the less you have of the other, and most people seem to favour the former until the lack of the latter affects them in some way.

Anyway, to Sage, archives, and pruning old data.

That 2003 one is interesting - because a long time back I dealt with a company who was in that situation. They had a huge amount of data in it, going back many years. Some functions were ridiculously slow, and there were problems showing up on the data validation tool. It was Sage 50 Professional, but I can't remember which version and for some reason, the option to clear old data didn't work; it would only remove a very small fraction of the relevant data. I suspect the data files were so big that it just couldn't cope.

My recommendation was to backup, run off all the key reports, and start afresh, keying in just the opening balances/live data.

As an aside, a downside with archiving is that it does mean the backups just get bigger and bigger each year. If there are no yearly archives, and instead data is pruned and backups for each year taken and kept on hand for access purposes, the backups don't get quite so big. The flip side is that it's less convenient to access the data for those prior years. (So there's another variation on that problem: Smaller backups versus convenience!)