Calibration and measurement are pillars of science; the same principle does not apply to the star ratings of hotels. Last week, I spent two nights in a five-star hotel in Switzerland; a few days later I spent two nights in a five-star hotel in Bulgaria. Five-stars here does not equal five-stars there.

From the outset, it is fair to say that it does not seem that there is any internationally-understood standard of what five stars mean. Assignments as a journalist have admitted me to many hotels on four continents around the world, and four of the five-star hotels in which I have stayed easily spring to mind as the "best" - in Sydney, Singapore, Berlin and Cape Town (nervous and hopeful hotel-keepers please note, in this blog no hotel is going to be mentioned by name; commercial endorsements or condemnations are not the point).

(I also wish to point out to any younger readers who may read this and believe that journalism is an entrée to a five-star lifestyle that one assignment found me in a remote hotel in Tanzania where my room boasted neither a mattress on the rusty bed frame nor, for that matter, a door; and a hotel in Namibia where in mid-winter the only form of heating was an electric blanket, entirely useless for all the time one was not underneath it, cowering from the desert cold. To say nothing of the countless sleepless nights, sans bed, that this career has meant. Generally, kids, journalism may get you into five-star hotels, but does not necessarily mean that you can afford to take anything from the mini-bar.)

And so to Switzerland, where just like the hotel I was to stay in a few days later in Bulgaria, the establishment was recently-opened. The receptionist was a model of warm courtesy, asking whether I would prefer a room with a shower or a bath, smoking or non-smoking and given that the hotel had adopted three different design styles for its interiors, which I would prefer. The merest formality of a glance at my passport - none of the nonsense of Bulgaria of holding my identity card at reception for hours or even overnight.

Security. The lift would operate only when I inserted my key card into a slot, and then would agree only to take me to my floor, no other. As may be expected, the room passed the test of my long-established routine four-point checklist immediately on putting down my luggage - that the phone works (a journalistic necessity), the taps run, the loo flushes and the television works. These days, one may add, a fifth check, whether the wi-fi works. The television displayed a touch that I first saw elsewhere more than a dozen years ago, a welcome message by name.

Nor was anything else lacking. Kettle, coffee maker, complementary coffee and tea (three varieties, happily including Rooibos) sachets, iron, ironing board and the full range of "smells and gels" toiletries, in-room safe, hairdryer, dressing gown and disposable slippers. An enormous bed boasting pillows of varying sizes, while the three gentle tones of the décor went well with the cutting-edge interior design. A final nice touch was the placing of the shower in the bathroom, making it possible to, through the alternating frosted and clear glass, continue to watch cable news while in the shower (all right, if you're the right height; I am 6' 2"). The mini-bar operating by a sensory reader that noted items being removed, so no need to fill out a little form.

Back at reception, the polite, trilingual young man was delighted to recommend a good place to find a restaurant in the city, giving clear directions and marking the place on a complementary guidebook. He did not, as has happened in other hotels in other cities, try to shepherd me to one of the hotel's own restaurants. I did breakfast there though, and the breakfast choice was impressive indeed, though for 37 Swiss francs (about 24 euro) it should have been.

Bulgaria, and a newish five-star hotel, not in Sofia and not in one of the country's best-known winter resorts. A greeting at reception by no means anywhere near the level of courtesy and warmth evidenced a few days earlier in Switzerland, and an identity card that spent 48 hours at reception because it was forgotten there after being temporarily confiscated. No offer to assist with luggage, and a vague hand wave and some general directions about which corridor to follow to the room. None of this should be exaggerated to be actual discourtesy, but in too many hotels in Bulgaria there is scant difference between received at reception and checking in at a dentist's waiting room, although at the dentist's you do not have to leave your identity card overnight.

Security. After two nights, I discovered that the door did not actually lock properly, so the whole key card business had been rather academic. But I rush ahead. As to my five-point checklist, no quibble except that the wi-fi was slightly patchy in effectiveness and speed. No ironing board, no iron, no kettle, no coffee, no tea, but a nice sharp pencil was thoughtfully provided to fill in the mini-bar form. No view from the shower to the room or vice versa, just a solid wall, so a potential loss of appeal for those addicted to cable news and, for that matter, to voyeurism. As to the interior, while it was nice enough, it was clear that neither the imagination nor the budget of its Swiss counterpart had been lavished on the design.

There were dressing gowns, slippers, a selection of toiletries smaller than in Switzerland, and while amid the Alps the TV in the room had offered channels in five languages including three news channels in English, Bulgaria offered four languages and no news channels in English (thus I watched news in the two languages that I could follow without effort, Bulgarian and German, but that's not the point).

Breakfast was included in the room price, though the choice was on a scale of about a fifth of the Swiss standard and oddly, one had to pay separately for coffee or any soft drink other than the weak juices available in the dispensers at the buffet. While all dining areas and bars in the Swiss hotel were non-smoking, the Bulgarian restaurant was fully non-smoking at breakfast and fully smoking, with no restricted areas, at lunch. Both hotels, by the way, were part of chains, although the Swiss one was part of one that is a brand known globally, the Bulgarian one a member of an outfit that is not quite a household name.

Yes, Switzerland is steeped in the tradition of hospitality, while Bulgaria's hotel industry varies wildly in quality, and of course Switzerland's GDP and tourist and business traveller client base make higher standards not only possible but essential. In the end, I would rate that particular Bulgarian five-star hotel as the equivalent of, say, one of South Africa's business and tourist three-star hotels. In any given country, a top star rating only means that an establishment has a rating of the maximum number of stars, not that it should be held up to the expectations normal in other countries.